As filed with the Securities and Exchange Commission on August 6, 2004

FORM S-4

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

MidSouth Bancorp, Inc.

102 Versailles Blvd.
Lafayette, Louisiana 70501
(337) 237-8343

       APPROXIMATE DATE OF COMMENCEMENT OF PROPOSED SALE TO THE PUBLIC: As soon as practicable after the effective date of this registration statement and the satisfaction or waiver of all other conditions to the merger described in the proxy statement/prospectus.

       If the securities being registered on this Form are being offered in connection with the formation of a holding company and there is compliance with General Instruction G, please check the following box. o

       If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

       If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

CALCULATION OF REGISTRATION FEE

     THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE OR DATES AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT SHALL FILE A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THIS REGISTRATION STATEMENT SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH SECTION 8(a) OF THE SECURITIES ACT OF 1933 OR UNTIL THIS REGISTRATION STATEMENT SHALL BECOME EFFECTIVE ON SUCH DATE AS THE COMMISSION, ACTING PURSUANT TO SAID SECTION 8(a), MAY DETERMINE.

LAMAR BANCSHARES, INC.

PROXY STATEMENT FOR SPECIAL MEETING OF SHAREHOLDERS
TO BE HELD                                         , 2004

MIDSOUTH BANCORP, INC.

PROSPECTUS

COMMON STOCK

Dear Shareholder:

     You are cordially invited to attend a special meeting of shareholders of Lamar Bancshares, Inc. to be held on                                         , 2004, at 4:00 p.m. at the offices of Lamar Bancshares, Inc., 555 N. Dowlen Road, Beaumont, Texas.

     At the meeting, you will be asked to vote upon a proposal to approve an Agreement and Plan of Merger dated as of May 27, 2004, between Lamar Bancshares, Inc. and MidSouth Bancorp, Inc. The merger agreement provides that Lamar Bancshares, Inc. will be merged into MidSouth Bancorp, Inc. In addition, you may be asked to vote upon a proposal to approve the adjournment of the special meeting, if necessary, to solicit additional proxies if there are not sufficient votes at the time of the meeting to approve the merger agreement. A proxy card is enclosed for your use in voting, or you may attend the special meeting and vote in person.

     If the merger is approved, each outstanding share of your common stock will be converted into cash and MidSouth Bancorp, Inc. common stock, which trades on the American Stock Exchange under the symbol MSL. On                     , 2004, the closing sales price of MidSouth’s common stock was $                    . Of course, there is no assurance as to the market value of MidSouth’s common stock on the date the proposed merger is completed.

     The proxy statement/prospectus gives you detailed information about the merger. You should read it carefully. It is a proxy statement that Lamar Bancshares, Inc. is using to solicit proxies for use at its special meeting of shareholders. It is also a prospectus relating to MidSouth’s issuance of shares of its common stock in connection with the merger.

     It is very important that your shares be represented at the meeting, regardless of whether you plan to attend in person. To assure that your shares are represented, please sign, date and return the enclosed proxy to Lamar Bancshares, Inc. in the enclosed postage-prepaid envelope. If you attend the meeting, you may revoke your proxy and vote your shares in person.

     The board of directors is enthusiastic about the merger and the strength and capabilities expected from the combined institutions, and unanimously recommends that you vote FOR approval of the merger.

Very truly yours,                              

NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES REGULATOR OR OTHER GOVERNMENTAL AGENCY HAS APPROVED OR DISAPPROVED THE MIDSOUTH BANCORP, INC. COMMON STOCK TO BE ISSUED IN THE MERGER OR DETERMINED IF THIS PROXY STATEMENT/ PROSPECTUS IS ACCURATE OR ADEQUATE. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

THE SECURITIES OFFERED THROUGH THIS DOCUMENT ARE NOT DEPOSITS, SAVINGS ACCOUNTS OR OTHER OBLIGATIONS OF A DEPOSITORY INSTITUTION AND ARE NOT INSURED BY THE FEDERAL DEPOSIT INSURANCE CORPORATION OR ANY OTHER GOVERNMENTAL AGENCY.

     This proxy statement/prospectus is dated                     , 2004 and is first being mailed to shareholders of Lamar Bancshares, Inc. on or about                     , 2004.

LAMAR BANCSHARES, INC.
555 N. Dowlen Road
Beaumont, Texas 77706

NOTICE OF SPECIAL MEETING OF SHAREHOLDERS

Beaumont, Texas
                    , 2004

     A special meeting of shareholders of Lamar Bancshares, Inc. will be held on                     , 2004, at 4:00 p.m., local time, at the offices of Lamar Bancshares, Inc., 555 N. Dowlen Rd., Beaumont, Texas, to vote upon the following matters:

     1. A proposal to approve an Agreement and Plan of Merger pursuant to which, among other things, Lamar Bancshares, Inc. will merge into MidSouth Bancorp, Inc., and on the effective date of the merger each outstanding share of common stock of Lamar Bancshares, Inc. will be converted into the right to receive shares of MidSouth Bancorp, Inc. common stock and cash;

     2. A proposal to adjourn the meeting to a later date or dates, if necessary, to permit further solicitation of proxies if there are not sufficient votes at the time of the meeting to approve the merger agreement; and

     3. Such other matters as may properly come before the special meeting or any adjournments thereof.

     Only shareholders of record at the close of business on                     , 2004, are entitled to notice of and to vote at the special meeting.

     Dissenting shareholders who comply with the procedural requirements of the Texas Business Corporation Act will be entitled to receive payment of the fair cash value of their shares.

     Your vote is important regardless of the number of shares you own. Whether or not you plan to attend the meeting, please mark, date and sign the enclosed proxy and return it promptly in the enclosed stamped envelope. Your proxy may be revoked by appropriate notice to Lamar Bancshares, Inc.’s Secretary at any time prior to the voting thereof.

By Order of the Board of Directors

TABLE OF CONTENTS

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QUESTIONS AND ANSWERS ABOUT VOTING PROCEDURES
FOR THE SPECIAL MEETING

Please do not send in your stock certificates with the proxy card.

If you did vote through a broker, you must follow directions you receive from your broker to change your vote.

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SUMMARY

     This summary highlights selected information from this document and may not contain all of the information that is important to you. To understand the merger fully and for a more complete description of the legal terms of the merger, you should read carefully this entire document and the other documents to which we have referred you. See “Where You Can Find More Information” beginning on page 12. Page references are included in this summary to direct you to a more complete description of the topics.

The Companies

     MidSouth Bancorp, Inc., a Louisiana corporation, is a bank holding company that owns all of the outstanding stock of MidSouth National Bank. Both companies’ principal executive offices are at 102 Versailles Boulevard, Lafayette, Louisiana 70501, and their telephone number is (337) 237-8343.

     Lamar Bancshares, Inc. is a Texas corporation that owns all the stock of Lamar Delaware Financial Corporation, which in turn owns all the stock of Lamar Bank. Its principal executive offices are at 555 North Dowlen Road, Beaumont, Texas 77706, and its telephone number is (409) 838-4781.

     For where you can find more information about these companies, please see “Where You Can Find More Information” beginning on page 12.

The Special Meeting

     Date; Voting. A special meeting of shareholders of Lamar Bancshares, Inc. will be held on                     , 2004, as described in the accompanying Notice of Special Meeting of Shareholders. Only record holders of the common stock of Lamar Bancshares, Inc. on July 1, 2004 are entitled to notice of and to vote at the meeting. On that date there were 222,339 shares of Lamar Bancshares, Inc. common stock outstanding, each of which is entitled to one vote on each matter properly to come before the meeting. See “Introductory Statement” beginning on page 13.

     Purpose. The purpose of the meeting is to vote upon a proposal to approve an Agreement and Plan of Merger that will merge Lamar Bancshares, Inc. into MidSouth Bancorp, Inc. Shareholders of Lamar Bancshares, Inc. will receive shares of Common Stock of MidSouth Bancorp, Inc. and cash for each Lamar Bancshares, Inc. share, as described below under “Conversion of Lamar Bancshares, Inc. Common Stock” beginning on page 24.

     Vote Required. The merger agreement must be approved by a two-thirds vote of the Lamar Bancshares, Inc. common stock present at the special meeting and eligible to vote. Directors and executive officers of Lamar Bancshares, Inc. who own an aggregate of 111,107 shares, or approximately 49.75% of the outstanding Lamar Bancshares, Inc. common stock, have agreed, subject to certain conditions, to vote in favor of the merger agreement.

Material Federal Income Tax Consequences (page 31)

     Each Lamar Bancshares, Inc. shareholder should not recognize gain or loss for the merger consideration received except with respect to the receipt of cash. BECAUSE OF THE COMPLEXITY OF THE TAX LAWS, EACH SHAREHOLDER SHOULD CONSULT HIS TAX ADVISOR CONCERNING THE APPLICABLE FEDERAL, STATE AND LOCAL INCOME TAX CONSEQUENCES OF THE MERGER.

Opinion of Lamar Bancshares, Inc.’s Financial Advisor (page 16)

     On April 6, 2004, The Bank Advisory Group, L.L.C., financial advisor to Lamar Bancshares, Inc. provided an oral presentation and opinion to the board of directors of Lamar Bancshares, Inc. that, as of March 2, 2004, based on and subject to the various assumptions made, the factors considered, the review undertaken and the limitations stated in the opinion, the merger consideration is fair to the holders of Lamar Bancshares, Inc. common stock from a financial point of view.

     The Bank Advisory Group’s opinion and presentation to the Lamar Bancshares, Inc. board of directors were among the many factors taken into consideration by the Lamar Bancshares, Inc. board of directors in making its determination to approve and to recommend that Lamar Bancshares, Inc. shareholders approve the merger. The

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Bank Advisory Group’s written opinion is attached as Appendix A to this proxy statement/prospectus. The opinion sets forth assumptions, limitations and matters considered in the review undertaken in connection with the opinion. The opinion does not constitute a recommendation by The Bank Advisory Group to you as to whether or not you should vote in favor of the merger or as to any other matter relating to the merger. You should read the opinion, which is attached as Appendix A, carefully and in its entirety.

Recommendation of Lamar Bancshares, Inc.’s Board of Directors (page 16)

     The financial and other terms of the merger agreement were arrived at through arm’s length negotiations between representatives of the companies. The board of directors of Lamar Bancshares, Inc. believes that the merger agreement is in the best interests of shareholders, has approved the merger agreement and unanimously recommends to shareholders the approval of the merger as set forth in the merger agreement.

The Merger Agreement (page 15)

     Conversion of Lamar Bancshares, Inc. Common Stock (page 24). On the effective date of the merger, subject to adjustments as discussed below, each outstanding share of Lamar Bancshares, Inc. common stock will be converted into:

     If on the closing date of the merger, the average closing sales price of MidSouth Bancorp, Inc. common stock on the American Stock Exchange for the ten trading days ending the day before such closing date (“Average Price”) is less than $31.50 per share, MidSouth Bancorp, Inc. shall adjust the conversion rate by multiplying the conversion rate by 1.07937. If on the closing date the Average Price exceeds $36.50, the conversion rate shall be adjusted by multiplying the conversion rate by 0.93151. If the Average Price is below $29.00, Lamar Bancshares, Inc. may terminate the merger transaction.

     Instead of issuing any fractional shares of MidSouth Bancorp, Inc. common stock, each shareholder of Lamar Bancshares, Inc. who would otherwise be entitled to a fractional share will receive a cash payment, without interest, equal to the fraction multiplied by the market value of a share of MidSouth Bancorp, Inc. common stock, as determined in accordance with the merger agreement.

     Conditions to the Merger (page 25). In addition to approval by the shareholders of Lamar Bancshares, Inc., consummation of the merger agreement is conditioned upon, among other things:

     The companies intend to consummate the merger as soon as practicable after all of the conditions have been met or waived. MidSouth Bancorp, Inc. has filed applications seeking the required regulatory approvals and expects to receive them by August 31, 2004. The approvals may not be obtained, by then or ever, and the other conditions to consummation of the merger agreement also may not be satisfied by such date or at all.

     Waiver, Amendment and Termination (page 28). Each of the companies may waive any of the conditions to its obligation to consummate the merger agreement other than shareholder and regulatory approvals. The merger

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agreement may also be amended at any time before or after shareholder approval by mutual agreement, but no amendment made after shareholder approval may alter the amount or type of consideration into which Lamar Bancshares, Inc. common stock will be converted or alter the merger agreement in a manner that would adversely affect any shareholder of Lamar Bancshares, Inc.

     The merger agreement may be terminated at any time before the merger is completed by mutual consent, or by either party:

     If Lamar Bancshares, Inc.’s board of directors determines that another proposal is more favorable to Lamar Bancshares, Inc.’s shareholders from a financial point of view than the proposed merger, it may terminate the merger agreement subject to MidSouth Bancorp, Inc.’s right of first refusal to submit a revised proposal.

Effect of Termination (page 29)

     If the merger agreement is terminated, the parties will be relieved of all obligations and liabilities, except that:

Financial Interests of Lamar Bancshares, Inc.’s Directors and Executive Officers in the Merger (page 29)

     Indemnification and Insurance (page 30). MidSouth Bancorp, Inc. has agreed to allow Lamar Bancshares, Inc. to purchase a continuation of its current officers’ and directors’ liability insurance for a period no longer than two years after the merger.

     MidSouth Bancorp, Inc. has also agreed to indemnify Lamar Bancshares, Inc.’s officers, directors and controlling persons against expenses and liabilities arising out of alleged misstatements or omissions in this document or the registration statement of which it is a part.

     Employment Agreements (page 30). On the effective date, Lonnie Weir, Ron D. Reed, Tim Zajonc, Travis Riley, David McCrady, Lance Gordon, Wilma Pace, Linda Ott Reed, Carole Malmberg, Jason Riley, Linda Allen and David Locke of Lamar Bank will continue as employees of Lamar Bank under employment agreements to be entered into with the consent of MidSouth Bancorp, Inc.

     Acceleration of Exercisability of Option’s (page 30). Prior to the consummation of the merger, Lamar Bancshares, Inc. will accelerate the exercisability of all previously granted Lamar Bancshares, Inc. stock options that are not currently exercisable.

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Any such options not exercised at the effective date of the merger will be cancelled, and the holders of such cancelled options will receive from MidSouth Bancorp, Inc., (a) a cash amount equal to the same consideration payable to shareholders of Lamar Bancshares, Inc. common stock under the merger agreement, less the exercise price for the options, plus (b) a cash amount equal to the amount of tax savings realized by MidSouth Bancorp, Inc. attributable to the consideration paid under (a) of this paragraph for the cancelled options.

     MidSouth Bancorp, Inc., Board of Directors (page 30). MidSouth Bancorp will cause to be appointed to its Board of Directors, to take office immediately after the effective date of the merger, Lonnie Weir, Ron Reed and Joe Tortorice, Jr., for the terms as set forth in the merger agreement.

Accounting Treatment (page 30)

     MidSouth Bancorp, Inc. will account for the merger as a purchase transaction. The purchase method of accounting involves adding Lamar Bancshares, Inc.’s assets and liabilities, estimated at their fair value at the effective date of the merger, to the recorded assets of MidSouth Bancorp, Inc. Therefore, the financial statements of MidSouth Bancorp, Inc. issued after the merger will reflect these values from Lamar Bancshares, Inc. and will not be restated retroactively to reflect the historical financial position or results of operations of Lamar Bancshares, Inc.

Dissenters’ Rights (page 34)

     Shareholders of Lamar Bancshares, Inc. will have the right to dissent from the merger agreement if they comply with the specific procedures required by the Texas Business Corporation Act. Dissenting shareholders who comply with the procedural requirements will be entitled to receive payment of the fair cash value of their shares.

PER SHARE FINANCIAL DATA OF LAMAR BANCSHARES, INC.

     Per share financial data for Lamar Bancshares, Inc. with respect to the fiscal year ended December 31, 2003, and the three months ended March 31, 2004, is set forth below.

PER SHARE FINANCIAL DATA OF MIDSOUTH BANCORP, INC.

     Per share financial data for MidSouth Bancorp, Inc. with respect to the fiscal year ended December 31, 2003, and the three months ended March 31, 2004, is set forth below.

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SELECTED UNAUDITED PRO FORMA COMBINED FINANCIAL INFORMATION

     The following tables present unaudited pro forma condensed combined financial statements for MidSouth Bancorp, Inc. after giving effect to the completion of MidSouth Bancorp Inc.’s proposed acquisition of Lamar Bancshares, Inc., with respect to the unaudited pro forma combined statement of condition as of March 31, 2004 and the related unaudited pro forma combined statements of income for the year ended December 31, 2003 and for the three months ended March 31, 2004.

     MidSouth Bancorp, Inc. intends to acquire all of the outstanding common stock of Lamar Bancshares, Inc. in a transaction to be accounted for under the purchase accounting method in accordance with accounting principles generally accepted in the United States of America. MidSouth Bancorp, Inc. will pay approximately $10,495,000 in cash and issue an estimated 370,000 shares (based on an assumed market value of MidSouth Bancorp, Inc. stock of $34 per share) of its common stock valued at approximately $12,555,000. MidSouth Bancorp, Inc. will also incur acquisition costs presently estimated at approximately $255,000. In connection with this acquisition, MidSouth Bancorp, Inc. intends to issue $6,000,000 of junior subordinated debentures (i.e., trust preferred stock) in order to fund a portion of the acquisition.

     The unaudited pro forma condensed combined financial statements gives the effect of the proposed acquisition under the purchase accounting method in accordance with accounting principles generally accepted in the United States of America. The unaudited pro forma combined financial statements of income combine the historical consolidated financial statements for MidSouth Bancorp, Inc. and Lamar Bancshares, Inc.

     The information as of March 31, 2004 and for the year ended December 31, 2003 and the three months ended March 31, 2004 is derived from:

     MidSouth Bancorp, Inc. anticipates that the acquisition will provide the combined company with future financial benefits, such as reduced operating expenses and opportunities to earn more revenue. However, MidSouth Bancorp, Inc. does not reflect these anticipated cost savings and benefits in the unaudited pro forma financial information. While the unaudited pro forma financial information is helpful in showing the financial characteristics of the combined companies, it is not intended to show how the combined companies would have actually performed had they been combined throughout the periods, or how the combined companies would perform in the future. MidSouth Bancorp, Inc. has included in the unaudited pro forma financial statements all the adjustments, consisting of normal recurring adjustments believed necessary for a fair statement of results of the historical periods.

     Given the information regarding the acquisition, the actual financial position and results of operations will differ, perhaps even significantly, from the unaudited pro forma amounts reflected below because, among other things:

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MidSouth Bancorp, Inc.
Unaudited Pro Forma Combined Statement of Condition
(Dollars in thousands except
share data)
As of March 31, 2004

See accompanying notes to unaudited pro forma condensed combined financial statements. MidSouth Bancorp, Inc.

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MidSouth Bancorp, Inc.
Unaudited Pro Forma Combined Statement of Income
Three Months Ended March 31, 2004
(Dollars in thousands except share data)

See accompanying notes to unaudited pro forma condensed combined financial statements.

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MidSouth Bancorp, Inc.
Unaudited Pro Forma Combined Statement of Income
Year Ended December 31, 2003
(Dollars in thousands except share data)

See accompanying notes to unaudited pro forma condensed combined financial statements.

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MidSouth Bancorp, Inc and Subsidiaries
Notes to Unaudited Pro Forma Condensed Combined Financial Statements.

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RECENT MARKET PRICES

     On May 26, 2004, the last business day before the public announcement of the merger agreement, the closing sales price for a share of MidSouth Bancorp, Inc. common stock, as quoted on the American Stock Exchange, was $30.00. On                     , 2004, the closing sales price for a share of MidSouth Bancorp, Inc. common stock, was $                    . No assurance can be given as to the sales price of a share of MidSouth Bancorp, Inc. common stock on the effective date of the merger.

     There is no established public trading market in which shares of Lamar Bancshares, Inc. common stock are regularly traded, nor are there any uniformly quoted prices for Lamar Bancshares, Inc. shares. The last sale of Lamar Bancshares, Inc. common stock prior to the execution of the merger agreement known to Lamar Bancshares, Inc.’s management occurred as a result of the exercise of stock options on March 22, 2004 at $62.75 per share, when the fair market value of the stock was $69.50 per share.

WHERE YOU CAN FIND MORE INFORMATION

     MidSouth Bancorp, Inc. files annual, quarterly and current reports, proxy statements and other information with the SEC. You may read and copy any of those filings at the SEC’s public reference room in Washington D.C., which is located at the following address: Public Reference Room, Judiciary Plaza, Room 1024, 450 Fifth Street, N.W., Washington, D.C. 20549.

     You can request copies of these documents, upon payment of a duplicating fee, by writing to the SEC. Please call the SEC at 1-800-SEC-0330 for further information on the operation of the SEC’s public reference rooms. The filings are also available to the public from document retrieval services and at the SEC’s Internet website (http://www.sec.gov).

     MidSouth Bancorp, Inc. has filed with the SEC a registration statement on Form S-4, and this document is part of that registration statement. As permitted by the SEC’s rules, this document does not contain all of the information you can find in the registration statement. The registration statement is available for inspection and copying as set forth above.

     The SEC allows MidSouth Bancorp, Inc. to “incorporate by reference” information into this document, which means important information can be disclosed to you by referring you to another document filed separately with the SEC. The information incorporated by reference is considered to be part of this document, except for any information contained directly in this document or in later filed documents incorporated by reference in this document.

     Copies of MidSouth Bancorp, Inc.’s Annual Report to Shareholders on Form 10-KSB for the year ended December 31, 2003 and Quarterly Report on Form 10-Q for the quarter ended March 31, 2004 incorporated by reference into this proxy statement/prospectus and should be read carefully in conjunction herewith. In addition, this proxy statement/prospectus incorporates by reference the documents set forth below that MidSouth Bancorp, Inc. has previously filed with the SEC and that contain important information about MidSouth Bancorp, Inc. and its business:

     MidSouth Bancorp, Inc. also incorporates by reference additional documents that may be filed with the SEC between the date of this proxy statement/prospectus and the completion of the merger or the termination of the merger agreement (other than information in such future filings deemed, under SEC rules, not to have been filed). These include periodic reports, such as annual reports on Form 10-K, quarterly reports on Form 10-Q and current reports on Form 8-K, as well as proxy statements.

     Any statement contained in a document incorporated or deemed to be incorporated by reference shall be deemed to be modified or superseded to the extent that a statement contained herein or in any other document subsequently filed and incorporated or deemed to be incorporated by reference herein modifies or supersedes such statement. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this proxy statement/prospectus.

     You may request a copy of all documents incorporated by reference in this document but not otherwise accompanying this document, as well as the merger agreement, at no cost, by writing or telephoning MidSouth Bancorp, Inc. at the following address:

102 Versailles Boulevard
Lafayette, Louisiana 70501
(337) 237-8343

     To obtain timely delivery, you should request desired information no later than five business days before the date of the special meeting, or by                     , 2004.

     You should rely only on the information contained or incorporated by reference in this document. Neither MidSouth Bancorp, Inc. nor Lamar Bancshares, Inc. has authorized anyone else to provide you with information that is different from that which is contained in this document. Moreover, neither MidSouth Bancorp, Inc. nor Lamar Bancshares, Inc. is making an offer to sell or soliciting an offer to buy any securities other than the MidSouth Bancorp, Inc. common stock to be issued by MidSouth Bancorp, Inc. in the merger, and neither MidSouth Bancorp,

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Inc. nor Lamar Bancshares, Inc. is making an offer of such securities in any state where the offer is not permitted. The information contained in this document speaks only as of its date unless the information specifically indicates that another date applies.

INTRODUCTORY STATEMENT

General

     This proxy statement/prospectus is furnished to the shareholders of Lamar Bancshares, Inc. in connection with the solicitation of proxies on behalf of Lamar Bancshares, Inc.’s board of directors for use at a special meeting of shareholders of Lamar Bancshares, Inc. to be held on the date and at the time and place specified in the accompanying notice.

     Lamar Bancshares, Inc. and MidSouth Bancorp, Inc. have each supplied all information with respect to it and its consolidated subsidiaries.

Purpose of the Meeting

     The purpose of the meeting is to consider and vote upon a proposal to approve an Agreement and Plan of Merger between Lamar Bancshares, Inc. and MidSouth Bancorp, Inc., pursuant to which, among other things, Lamar Bancshares, Inc. will merge into MidSouth Bancorp, Inc., and each outstanding share of common stock of Lamar Bancshares, Inc. will be converted into the right to receive shares of common stock of MidSouth Bancorp, Inc., and cash.

     At the meeting, shareholders will also be asked, if necessary, to consider and vote upon a proposal to adjourn the meeting to permit further solicitation of proxies if there are not sufficient votes at the time of the meeting to approve the merger agreement and to consider any other matters that may be properly submitted for a vote at the meeting.

Shares Entitled to Vote; Quorum; Vote Required

     Only holders of record of Lamar Bancshares, Inc. common stock at the close of business on July 1, 2004 are entitled to notice of and to vote at the meeting. On that date, there were 222,339 shares of Lamar Bancshares, Inc. common stock outstanding, each of which is entitled to one vote on each matter properly brought before the meeting. The presence at the meeting, in person or by proxy, of the holders of a majority of the outstanding shares of common stock of Lamar Bancshares, Inc. is necessary to constitute a quorum.

     The merger agreement must be approved by the affirmative vote of the holders of at least two-thirds of the Lamar Bancshares, Inc. common stock present, in person or by proxy, at the meeting. An abstention will have the effect of a vote against the merger agreement. A broker “non-vote” in person or by proxy will be counted for purposes of determining a quorum but will not be counted in determining the voting power present with respect to the vote on the merger agreement and thus will have no effect on the vote.

     The affirmative vote of a majority of the votes cast on the matter at the meeting is required to approve the proposal to adjourn the meeting if necessary to permit further solicitation of proxies on the proposal to approve the merger agreement and any other matter properly submitted to shareholders for their consideration at the meeting. Because of the vote required for the proposal to adjourn the meeting, abstentions and broker “non-votes” will have no effect on this proposal.

     Directors and executive officers of Lamar Bancshares, Inc. beneficially owning an aggregate of 111,107 shares, or approximately 49.75% of the outstanding Lamar Bancshares, Inc. common stock, have agreed to vote in favor of the merger agreement.

Solicitation, Voting and Revocation of Proxies

     In addition to soliciting proxies by mail, directors, officers and other employees of Lamar Bancshares, Inc., and MidSouth Bancorp, Inc., without receiving additional compensation, may solicit proxies by telephone, fax, e-

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mail and in person. Arrangements will also be made with brokerage firms and other custodians, nominees and fiduciaries to forward solicitation materials to the beneficial owners of shares of Lamar Bancshares, Inc. common stock, and Lamar Bancshares, Inc. will reimburse such parties for reasonable out-of-pocket expenses incurred. The cost of soliciting proxies is being paid by Lamar Bancshares, Inc.

     The form of proxy that accompanies this proxy statement/prospectus permits each holder of record of Lamar Bancshares, Inc. common stock on the record date to vote on all matters that properly come before the meeting. Where a shareholder specifies his choice on the accompanying form of proxy with respect to the proposal to approve the merger agreement, the shares represented by the proxy will be voted in accordance with that specification. If no specification is made, the shares will be voted in favor of the merger agreement and to adjourn the meeting, if necessary. If you do not sign and return a proxy and specify on the proxy an instruction to vote against the merger agreement, you will not be able to exercise dissenters’ rights unless you attend the meeting in person and vote against the merger agreement and give written notice of your dissent from the merger agreement at or prior to the meeting. See “Dissenters’ Rights.”

     A proxy may be revoked at any time before it is voted by:

RISK FACTORS RELATING TO THE MERGER

     In addition to the other information contained in or incorporated by reference into this document, including without limitation, MidSouth Bancorp, Inc.’s Annual Report on Form 10-KSB for the fiscal year ended December 31, 2003, and its Quarterly Report on Form 10-Q for the three months ended March 31, 2004, you should carefully consider the following risk factors in deciding whether to vote to approve the merger agreement.

Because the market price of MidSouth Bancorp, Inc. Common Stock will fluctuate, Lamar Bancshares, Inc. shareholders cannot be sure of the number of shares they will receive.

     Upon completion of the merger, each share of Lamar Bancshares, Inc. common stock will be converted into shares of MidSouth Bancorp, Inc. common stock and cash pursuant to the terms of the merger agreement. The number of shares of MidSouth Bancorp, Inc. to be received by Lamar Bancshares, Inc. shareholders will be based on the average closing sales price of MidSouth Bancorp, Inc. common stock on the AMEX during the ten trading days ending on the day before the completion of the merger. This average closing sales price may vary from the actual closing sales price of MidSouth Bancorp, Inc. common stock on the date we announced the merger, on the date that this proxy statement-prospectus was mailed to Lamar Bancshares, Inc. shareholders, and on the date of the special meeting of the Lamar Bancshares, Inc. shareholders. Any ultimate change in the closing sales price of MidSouth Bancorp, Inc. common stock during the ten days before completion of the merger will affect the number of shares that Lamar Bancshares, Inc. shareholders will receive upon completion of the merger. Stock price changes may result from a variety of factors, including general market and economic conditions, changes in our respective businesses, operations and prospects, and regulatory considerations. Many of these factors are beyond our control.

     Accordingly, at the time of the meeting, Lamar Bancshares, Inc. shareholders will not necessarily know or be able to calculate the number of shares they would receive or the exchange ratio used to determine the number of any shares of MidSouth Bancorp, Inc. common stock they would receive upon completion of the merger.

We may fail to realize the anticipated benefits of the merger.

     The success of the merger will depend, in part, on our ability to realize the anticipated cost savings and revenue enhancements from combining the businesses. To realize the anticipated benefits from the merger, we must successfully combine the businesses in a manner that permits those cost savings and revenue enhancements to be realized. If we are not able to achieve these objectives, the anticipated benefits of the merger may not be realized fully or at all or may take longer to realize than expected.

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     MidSouth Bank and Lamar Bank have operated separately and, after the completion of the merger, will continue to operate separately to a certain extent. It is possible, however, that the integration process could result in the loss of key employees, the disruption of each company’s ongoing businesses or inconsistencies in standards, controls, procedures and policies that adversely affect our ability to maintain relationships with clients, customers, depositors and employees or to achieve the anticipated benefits of the merger.

The market price of the shares of MidSouth Bancorp, Inc. common stock after the Merger may be affected by factors different from those affecting the shares of MidSouth Bancorp, Inc. currently.

     The businesses of MidSouth Bancorp, Inc., and Lamar Bancshares, Inc., differ in some respects (including geographic locations, market competition and asset size) and, accordingly, the results of operations of the combined company and the market price of the combined company’s shares of common stock may be affected by factors different from those currently affecting the independent results of operations of MidSouth Bancorp, Inc.

The volume of trading in MidSouth Bancorp, Inc., Common Stock is low, and shareholders who attempt to sell their shares may receive less than they expected.

     The average weekly trading volume of MidSouth Bancorp., Inc. common stock over the last three months has been 7,725 shares, or 1,545 shares per day. A shareholder of MidSouth Bancorp, Inc., seeking to sell any appreciable amount of his or her stock may not find sufficient buyers who will pay the current trading price of the stock as quoted on the Amex and, therefore, may have to sell at a lower price.

THE MERGER AGREEMENT

     The following brief description does not describe all of the terms of the merger agreement. We encourage you to obtain and read the merger agreement completely and carefully. It is the legal document that governs the merger.

Background of and Reasons for the Merger

     The Lamar Bancshares, Inc. Board of Directors periodically has reviewed Lamar Bank’s performance, compared its performance with that of certain relatively comparable institutions, reviewed the limited market activity in Lamar Bancshares, Inc.’s common stock, considered various business opportunities and strategies available to Lamar Bancshares, Inc. and discussed the general economic, regulatory, competitive and business pressures affecting Lamar Bancshares, Inc. In addition, the Lamar Bancshares, Inc. board, on an informal basis and during strategic planning sessions, would periodically review merger and acquisition activity in the banking industry.

     The Lamar Bancshares, Inc. Board of Directors met on April 6, 2004, to review the terms and conditions of the proposed merger. The Lamar Bancshares, Inc. Board of Directors carefully reviewed and considered, with the assistance of its financial advisor and legal counsel, the financial and legal aspects of the proposed merger, as set forth in MidSouth Bancorp, Inc.’s then proposed letter of intent. At a special meeting on May 27, 2004, the Lamar Bancshares, Inc. Board of Directors authorized execution of the merger agreement and the other related agreements and documents. Each director of Lamar Bancshares, Inc. also entered into a commitment agreement with MidSouth Bancorp, Inc. obligating them to vote their shares in favor of the merger agreement and against any other transaction, and agreeing to certain non-competition agreements.

     The Lamar Bancshares, Inc. Board of Directors has determined that the terms of the merger, the merger agreement, and the proposed issuance of MidSouth Bancorp, Inc. common stock and cash in connection with the merger are advisable and fair to, and in the best interest of, Lamar Bancshares, Inc. and its shareholders. In reaching its determination, the Lamar Bancshares, Inc. Board of Directors considered a number of factors. The Lamar Bancshares, Inc. board of directors did not assign any specific or relative weights to the factors considered, and individual directors may have given different weights to different factors. The material factors considered were as follows:

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     Lamar Bancshares, Inc.’s board of directors unanimously recommends that the holders of Lamar Bancshares, Inc. common stock vote “FOR” approval of the merger as set forth in the Agreement and Plan of Merger.

Opinion of Lamar Bancshares, Inc.’s Financial Advisor

     Pursuant to an engagement letter dated February 25, 2004, signed and executed by Lamar Bancshares, Inc. on March 8, 2004, Lamar Bancshares, Inc. engaged The Bank Advisory Group, L.L.C. to act as an independent financial advisor to the Lamar Bancshares, Inc. board of directors in connection with the proposed sale of Lamar Bancshares, Inc. to MidSouth Bancorp, Inc. Specifically, based on The Bank Advisory Group’s reputation and qualifications in evaluating financial institutions, the Lamar Bancshares, Inc. board of directors requested that The Bank Advisory Group render advice and analysis in connection with the merger, and to provide opinions with regard to the fairness – from the perspective of the shareholders of Lamar Bancshares, Inc. common stock – of the financial terms of the merger.

     Based on all factors that The Bank Advisory Group deemed relevant and assuming the accuracy and completeness of the information and data provided, The Bank Advisory Group rendered a written fairness opinion, dated July 21, 2004 – which is set forth in Appendix A to this proxy statement/prospectus – to the effect that the terms of the proposed merger, including, without limitation, the gross consideration equaling the sum of (i) a number of shares of MidSouth Bancorp, Inc. common stock equal to $12,556,351 divided by $34; plus (ii) $10,494,000 in cash, offered in exchange for all of the outstanding common shares and outstanding stock options of Lamar Bancshares, Inc. on the effective date, is fair, from a financial point of view, to the shareholders of Lamar Bancshares, Inc. common stock.

     No limitations were imposed by the Lamar Bancshares, Inc. board of directors upon The Bank Advisory Group with respect to the analysis, conclusions, opinions or procedures followed in rendering the July 21, 2004

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fairness opinion. The Bank Advisory Group does not, and its officers, directors and shareholders do not, own any shares of Lamar Bancshares, Inc. common stock or MidSouth Bancorp, Inc. common stock; nor does The Bank Advisory Group make a market in the stock of Lamar Bancshares, MidSouth Bancorp, Inc., or any other publicly-traded security, financial or otherwise.

     The full text of the July 21, 2004 fairness opinion – which sets forth certain assumptions made, matters considered, and limits on the review undertaken by The Bank Advisory Group – is set forth in Appendix A to this proxy statement/prospectus. Lamar Bancshares, Inc. shareholders are urged to read the July 21, 2004 fairness opinion in its entirety. The July 21, 2004 fairness opinion, addressed to the Lamar Bancshares, Inc. board of directors, covers only the fairness of the financial terms of the merger, from a financial point of view, to the shareholders of Lamar Bancshares, Inc. common stock. The financial terms include, but are not limited to, the gross consideration of a the sum of (i) a number of shares of MidSouth Bancorp, Inc. common stock equal to $12,556,351 divided by $34; plus (ii) $10,494,000 in cash in exchange for all of the outstanding common shares and outstanding stock options of Lamar Bancshares, Inc. at the effective time of the merger.

     The July 21, 2004 fairness opinion does not constitute an endorsement of the merger. The Bank Advisory Group was not asked to consider, and the July 21, 2004 fairness opinion does not address, the relative merits of the proposed sale of Lamar Bancshares, Inc. to MidSouth Bancorp, Inc. as compared to alternative business strategies that might exist for Lamar Bancshares, Inc. or the effect of any other transaction(s) in which Lamar Bancshares, Inc. might engage. In furnishing the July 21, 2004 fairness opinion, The Bank Advisory Group does not purport to be an expert with respect to the registration statement of which this proxy statement/prospectus is part within the meaning of the term “expert” as used in, or that would come within the category of persons whose consent is required under, the Securities Act of 1933, as amended, or the rules and regulations of the Securities and Exchange Commission promulgated thereunder. The summary of the procedures and analysis performed and assumptions used by The Bank Advisory Group set forth in this proxy statement/prospectus is qualified in its entirety by reference to the text of the July 21, 2004 fairness opinion, which is set forth in Appendix A to this proxy statement/prospectus and incorporated herein by reference. Neither this discussion nor the July 21, 2004 fairness opinion constitute a recommendation by the Bank Advisory Group to any shareholder of Lamar Bancshares, Inc. as to how such shareholder should vote at the shareholders’ meeting held for the purpose of voting on the merger.

     Summary of Information Reviewed. The Bank Advisory Group, in connection with the issuance of the July 21, 2004 fairness opinion reviewed, among other things, the following Lamar Bancshares, Inc. information:

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In addition, The Bank Advisory Group reviewed the following MidSouth Bancorp, Inc. information:

The Bank Advisory Group, in connection with the merger, reviewed, among other things, the following items:

     In connection with its review, The Bank Advisory Group has relied upon the information provided by the management of Lamar Bancshares, Inc. and MidSouth Bancorp, Inc., or otherwise publicly-available and reviewed by The Bank Advisory Group, as being complete and accurate in all material respects. The Bank Advisory Group

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met with the management of Lamar Bancshares, Inc. and MidSouth Bancorp, Inc. for the purpose of discussing the relevant information that has been provided to The Bank Advisory Group.

     The Bank Advisory Group has not verified, through independent inspection or direct examination, the specific assets or liabilities of Lamar Bancshares, Inc., MidSouth Bancorp, Inc. or their subsidiary banks. The Bank Advisory Group has assumed that there have been no material changes in the assets, financial condition, results of operations, or business prospects of Lamar Bancshares, Inc. and MidSouth Bancorp, Inc. since the date of the last financial statements made available to The Bank Advisory Group. The Bank Advisory Group has also assumed that there are no material off-balance sheet assets or liabilities for Lamar Bancshares, Inc. or MidSouth Bancorp, Inc. that are not otherwise disclosed in the financial information either disclosed or publicly-available.

     The Bank Advisory Group is not an expert in the evaluation of loan portfolios for purposes of assessing the adequacy of the allowances for losses with respect thereto, and The Bank Advisory Group assumed, with Lamar Bancshares, Inc.’ consent, that such allowances for each of Lamar Bancshares, Inc. and MidSouth Bancorp, Inc. are in the aggregate adequate to cover such losses. In addition, The Bank Advisory Group did not assume responsibility for reviewing any individual credit files, or for making an independent evaluation, appraisal or physical inspection of any of the assets or liabilities (contingent or otherwise) of Lamar Bancshares, Inc. or MidSouth Bancorp, Inc., nor was The Bank Advisory Group furnished with any such appraisals. Finally, The Bank Advisory Group’s opinions were based on economic, monetary and market and other conditions in effect as of the date of the fairness opinions. Accordingly, although subsequent developments may affect The Bank Advisory Group’s opinions, The Bank Advisory Group has not assumed any obligation to update, revise or reaffirm such opinions.

     The Bank Advisory Group did not discuss with the independent accountants for either Lamar Bancshares, Inc. or MidSouth Bancorp, Inc. any financial reporting matters with respect to Lamar Bancshares, Inc., MidSouth Bancorp, Inc., the merger, or the merger agreement. Lamar Bancshares, Inc. informed The Bank Advisory Group, and The Bank Advisory Group assumed, that the merger would be recorded as a “purchase” under generally accepted accounting principles. The Bank Advisory Group assumed that the merger would be consummated in a manner that complies in all respects with the applicable provisions of the Securities Act of 1933, the Securities Exchange Act of 1934 and all other applicable federal and state statutes, rules and regulations.

     With respect to the financial forecasts for Lamar Bancshares, Inc., The Bank Advisory Group assumed for purposes of its opinion, and with Lamar Bancshares, Inc.’ consent, that the forecasts were reasonably prepared on bases reflecting the best available estimates at the time of preparation as to the future financial performance of Lamar Bancshares, Inc., and that they provided a reasonable basis upon which The Bank Advisory Group could form its opinion.

     Professional Fees Paid to The Bank Advisory Group. Since May 2000, and prior to its retention for this specific assignment, The Bank Advisory Group has provided financial services to Lamar Bancshares, Inc. in various capacities on an infrequent basis; however, the revenues derived from the delivery of such services are insignificant when compared to The Bank Advisory Group’s total gross revenues.

     For The Bank Advisory Group’s services as an independent financial analyst and advisor to Lamar Bancshares, Inc. in connection with the merger, Lamar Bancshares, Inc. has agreed to pay The Bank Advisory Group a professional fee approximating $110,000, of which $20,000 has been received by The Bank Advisory Group. Additionally, Lamar Bancshares, Inc. also has agreed to reimburse The Bank Advisory Group for reasonable out-of-pocket expenses. Furthermore, in connection with the merger, Lamar Bancshares, Inc. has agreed to indemnify The Bank Advisory Group, the officers, directors, employees, and shareholders of The Bank Advisory Group and assigns, heirs, beneficiaries and legal representatives of each indemnified entity and person. No portion of The Bank Advisory Group’s fee is contingent upon the conclusion reached in the July 21, 2004 fairness opinion; and, Lamar Bancshares, Inc.’ obligation to pay the remaining balance of the professional fee due to The Bank Advisory Group is not contingent upon the conclusion reached in the July 21, 2004 fairness opinion.

     The Bank Advisory Group has not previously provided any services to MidSouth Bancorp, Inc. and, thus, has never received any professional fees from MidSouth Bancorp, Inc.

     Financial Projections for Lamar Bancshares, Inc. The Bank Advisory Group developed stand-alone financial projections for Lamar Bancshares, Inc., which were derived by The Bank Advisory Group with input from

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management of Lamar Bancshares, Inc. However, the financial projections for Lamar Bancshares, Inc. represented The Bank Advisory Group’s independent assessment of a reasonable and defensible outlook for the future performance and condition of Lamar Bancshares, Inc. The financial projections were derived for a twelve-year period, 2004 – 2015, with specific focus given to the six-year period representing the years 2004 – 2009. In summary, the financial projections reflected total assets of Lamar Bancshares, Inc. growing at a rate of between 1.50% and 3.00% per annum. Return on average assets (converted to C corporation earnings through the application of a 36% federal income tax rate) for Lamar Bancshares, Inc. was projected to range between 1.02% and 1.22%, annually. The financial projections were presented to the Lamar Bancshares, Inc. board of directors at an April 6, 2004 meeting.

     The projection of future financial performance of Lamar Bancshares, Inc. (on a fully-diluted basis) allowed The Bank Advisory Group, and in turn, the Lamar Bancshares, Inc. Board of Directors, to compare, based on a number of assumptions, the potential future value of Lamar Bancshares, Inc. expressed in terms of today’s dollars (a present value basis) in relation to the transaction value per share of $95.99. This comparative analysis resulted in multiple scenarios. However, the vast majority of the scenarios, and all of the scenarios based on the most reasonable assumptions, revealed similar results. In summary, the analyses suggested that the transaction value per share of $95.99 exceeded the future potential value, when expressed on a present value basis, of Lamar Bancshares, Inc. common stock, based on a range of assumed earnings multiples applied to projected earnings per share of $6.67 and projected dividends per share of $6.00 for Lamar Bancshares, Inc. during 2009 (the last year of the projection period). Thus, this analysis provided support for the acceptance of the MidSouth Bancorp, Inc. offer of $23,382,725 in total consideration. The analysis revealed similar results when considering the projection years prior to 2009. The chart below briefly summarizes the analyses for the 2009 projection year:

     Likewise, the analyses suggested that the transaction value per share of $95.99 exceeded the future potential value (on a fully-diluted basis), when expressed on a present value basis, of Lamar Bancshares, Inc. common stock, based on a range of assumed equity multiples applied to projected core equity per share of $55.10 for Lamar Bancshares, Inc. at year-end 2009, the end of the six-year projection period. This analysis included assumed annual dividends per share of $6.00. Thus, this analysis provided further support for the acceptance of the MidSouth Bancorp, Inc. offer of $23,382,725 in total consideration. The analysis revealed similar results when considering the projection years prior to 2009. The chart below briefly summarizes the analyses:

     The projection of future financial performance of Lamar Bancshares, Inc. on a C corporation basis (assuming a federal tax rate of 36%) further allowed The Bank Advisory Group, and in turn the Lamar Bancshares, Inc. board of directors, to compare the projection of future dividend streams of Lamar Bancshares, Inc. shareholders on a stand-alone basis (assuming no merger with MidSouth Bancorp, Inc. and, thus, Lamar Bancshares, Inc. operating on a status quo basis with an annual dividend payout of $6.00 per share) versus the dividend stream Lamar Bancshares, Inc. shareholders likely would receive as MidSouth Bancorp, Inc. shareholders on a post-merger basis (with earnings per share for MidSouth Bancorp, Inc. based on the composite average of analysts’ estimates for 2004 – 2005, earnings per share growth thereafter consistent with stated goals for MidSouth Bancorp, Inc., and a dividend payout rate consistent MidSouth Bancorp, Inc.’s historical payout history). However, given that Lamar Bancshares,

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Inc. is an S corporation which historically paid and projects to pay cash dividends approximating 100% of net earnings; and, given that MidSouth Bancorp, Inc. is a growth-oriented publicly-traded banking organization which has historically paid cash dividends approximating 16% – 20% of net earnings, the comparative analysis of future dividend yields provide no reasonable basis for judging the financial fairness of the transaction value.

     Analysis of Selected Merger Transactions. The Bank Advisory Group maintains a sizable database of information pertaining to the prices paid for U.S. banks and their holding companies. This database includes transactions involving banking organizations operating throughout the United States, and provides comparable pricing and financial performance data for banking organizations acquired in the United States since 1989. The Bank Advisory Group has the capability of sorting the records by year or combinations of years to yield transactions involving similar banks. Similarities might include banks within a specific asset size range, banks within a specific state or geographic region, banks that generate a level of earnings as a percent of average assets (“return on average assets” or “ROA”) within a specified range, banks that have an equity-to-assets ratio within a certain range, or banks that sold for a specific form of consideration (cash or stock). The ability to produce specific groups of comparable banks facilitates making a valid comparative purchase price analysis.

     In deriving the comparable pricing analyses, as described below, it should be recognized that no other single company or transaction is identical to Lamar Bancshares, Inc. Accordingly, an examination of the results of the following comparative analysis is not mathematical; rather, it involves complex considerations and judgments concerning differences in financial and operating characteristics of the companies as well as other factors that could affect the public trading value and the announced acquisition prices of the companies to which Lamar Bancshares, Inc. is being compared.

     Price Multiples and Price Indices: The Bank Advisory Group considered transaction values for banking organizations located in all United States non-rural domiciles, reporting total assets between $75 million and $150 million, a return on assets (“ROA”) between 0.50% and 1.50%, a ratio of core capital-to-total assets between 8.00% and 14.00%, and acquired during 2002 through year-to-date 2004 (the “U.S. Peer Group”). The banking companies which comprise the U.S. Peer Group are listed below:

     The Bank Advisory Group compared Lamar Bancshares, Inc.’s financial fundamentals and the pricing values relating to the transaction value with the average financial fundamentals and average pricing values for the U.S. Peer Group. The comparative analysis revealed that the proposed merger equated to a transaction value for Lamar Bancshares, Inc. resulting in a purchase price as a percent of total assets (price-equity index) of 20.17, a level 2% lower than the 20.67 average for the U.S. Peer Group. The fully-diluted December 31, 2003 core equity-to-assets ratio for Lamar Bancshares, Inc. equaled 11.79%, a ratio that is 179 basis points and 18% higher than the average core equity-to-assets ratio of 10.00% for the U.S. Peer Group. Likewise, the fully-diluted four-quarter

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trailing return on average assets (“ROA”) for Lamar Bancshares, Inc. equaled 1.16%, a ratio that is 17 basis points and 17% higher than the average ROA of 0.99% for the U.S. Peer Group. Correspondingly, the fully-diluted four-quarter trailing return on average equity capital (“ROE”) for Lamar Bancshares, Inc. equaled 10.28%, a ratio that is 16 basis points and 2% higher than the average ROE of 10.12% for the U.S. Peer Group.

     Conversely, Lamar Bancshares, Inc.’s asset growth for the trailing four quarters equaled 5.38%, a ratio that is 905 basis points and 63% lower than the average of 14.43% for the U.S. Peer Group. Correspondingly, Lamar Bancshares, Inc. was located in the Beaumont/Port Arthur, Texas Metropolitan Statistical Area, which recorded total population of approximately 390 thousand in 2003. Each of the banking organizations contained within the U.S. Peer Group were located in Metropolitan Statistical Areas. The Metropolitan Statistical Areas represented by the U.S. Peer Group possessed an average population of 4.0 million and a mean population of 1.0 million in 2003. Moreover, the Beaumont/Port Arthur, Texas Metropolitan Statistical Area reported annual population growth of 1.27% during 2000 – 2003 and has projected annual population growth of 2.13% during 2003 – 2008, comparing well below the 3.92% and 6.08% respective averages for the Metropolitan Statistical Areas represented by the U.S. Peer Group.

     The valuation of an investment always considers, if not primarily focuses, on the future growth prospects of the earnings stream corresponding with the investment. Accordingly, the valuation of an investment is an inherently forward-looking process. The presence of inferior historical and projected growth indicators for Lamar Bancshares, Inc. clearly supports a higher average price index for the U.S. Peer Group as compared to those corresponding with the $23,382,725 transaction value for Lamar Bancshares, Inc. Therefore, the analysis set forth in the preceding paragraphs indicates that the transaction value for Lamar Bancshares, Inc., as measured by the price index described above, is reasonable and defensible. The table set forth immediately subsequent to this paragraph summarizes this comparative analysis, and highlights the Lamar Bancshares, Inc. transaction.

      Common Stock Indexed Price Multiples: The Bank Advisory Group also considered transaction values for profitable banking organizations acquired by publicly-traded banking organizations. Specifically, The Bank Advisory Group utilized profitable United States banking organizations acquired by publicly-traded banking organizations from January 2002 through year-to-date 2004, reporting total assets under $500 million, and where the form of consideration consisted of 100% common stock or a mixture of common stock and cash, and for which both price data and related financial information are publicly-available. The Bank Advisory Group termed these banking organizations the “Indexed Peer Group.”

     In order to derive indexed price multiples for the Indexed Peer Group, The Bank Advisory Group compared the price multiples calculated for each transaction value at the date of announcement relative to the market price multiples for the common stock of the relevant acquirer at the month-end prior to announcement date. Additionally, The Bank Advisory Group compared the price-to-assets index calculated for each transaction value at the date of announcement relative to the market price-to-assets index for the common stock of the relevant acquirer at the month-end prior to announcement date. The Bank Advisory Group then compared the average of the indexed price multiples and price-to-assets index for the Indexed Peer Group, segmented into quartiles by the indexed price-to-assets index, in relation to the indexed price multiples and price-to-assets index computed for the transaction value attributable to Lamar Bancshares, Inc. in connection with the merger, using the market price multiples for MidSouth Bancorp, Inc. common stock.

     The comparative analysis revealed that the transaction value resulted in a price-to-core equity multiple of

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1.71x for Lamar Bancshares, Inc., versus the 2.44x and 2.34x averages for the second and third quartiles of the Indexed Peer Group, and the 2.36x average for the entire Indexed Peer Group. Additionally, the comparative analysis revealed that the transaction value resulted in a price-to-earnings multiple of 17.89x for Lamar Bancshares, versus the 23.44x and 24.77x averages for the second and third quartiles of the Indexed Peer Group, and the 23.80x average for the entire Indexed Peer Group. Moreover, the comparative analysis revealed that the transaction value resulted in a price-to-assets index of 20.17 for Lamar Bancshares, Inc., versus the 21.67 and 20.95 averages for the second and third quartiles of the Indexed Peer Group, and the 21.04 average for the Indexed Peer Group. However, when the 20.17 price-to-assets index is compared relative to the 24.63 price-to-assets index for MidSouth Bancorp, Inc. common stock as of June 9, 2004, the transaction value equated to an indexed price-to-assets index of 81.9%, versus the 105.2% and 128.3% averages for the second and third quartiles of the Indexed Peer Group, and the 109.7% average for the entire Indexed Peer Group.

     The price-to-core equity transaction index of at 81.9% for Lamar Bancshares, Inc. is substantially lower than the averages computed for the Indexed Peer Group. However, that disparity is reasonable, and to be expected, when giving consideration to Lamar Bancshares, Inc.’s substantially higher core equity-to-assets ratio of 10.70% (as of December 31, 2003) in comparison with the 8.91% average for the Indexed Peer Group; and, giving consideration that the 3.28x price-to-book value multiple of MidSouth Bancorp, Inc. as of June 9, 2004 substantially exceeded the 2.16x average for the Indexed Peer Group. In brief terms, it generally follows that the higher the core equity-to-assets ratio, the lower the price-to-core equity multiple. That relationship holds true in the case of Lamar Bancshares, both in terms of the stated price-to-core equity and the indexed price-to-core equity transaction index at the transaction value. Furthermore, although the first quartile of the Indexed Peer Group reported the highest price-to-book value multiple (2.91x) and the MidSouth Bancorp, Inc. price-to-book value multiple of 3.28x exceeded the average for the first quartile of the Indexed Peer Group, the price-to-core equity transaction index of 81.9% for Lamar Bancshares, Inc. substantially exceeded the 72.6% average for the first quartile of the Indexed Peer Group.

The table set forth below summarizes the indexed price multiples analysis, and highlights the Lamar Bancshares, Inc. transaction.

     Informed Professional Opinion. The summaries set forth above do not purport to be a complete description of the analyses performed by The Bank Advisory Group. The Bank Advisory Group believes that its analyses and the summaries set forth above must be considered as a whole and that selecting a portion of its analyses and factors, without considering all analyses and factors, would create an incomplete view of the process underlying the analyses used by The Bank Advisory Group.

     In addition, The Bank Advisory Group may have given various analyses more or less weight than other analyses, and may have deemed various assumptions more or less probable than other assumptions, so that the

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ranges of valuations resulting from any particular analysis described above should not be taken to be The Bank Advisory Group’s view of the actual value of MidSouth Bancorp, Inc. common stock on a post-merger basis. The fact that any specific analysis has been referred to in the summary above is not meant to indicate that such analysis was given greater weight than any other analysis.

     In performing its analyses, The Bank Advisory Group made numerous assumptions with respect to industry performance, general business and economic conditions and other matters, many of which are beyond the control of both Lamar Bancshares, Inc. and MidSouth Bancorp, Inc. The analyses performed by The Bank Advisory Group are not necessarily indicative of actual values or actual future results, which may be significantly more or less favorable than suggested by such analyses. Such analyses were prepared in connection with The Bank Advisory Group’s determination of the fairness of the financial terms of the merger, from a financial point of view, to the shareholders of Lamar Bancshares, Inc. common stock. The analyses do not purport to be appraisals or to reflect the prices at which a company might actually be sold or the prices at which any securities may trade at the present time or any time in the future. The forecasts utilized by The Bank Advisory Group in certain of its analyses are based on numerous variables and assumptions which are inherently unpredictable and, therefore, not certain to become reality. Accordingly, actual results could vary significantly from those contemplated in such forecasts.

     The Bank Advisory Group is of the belief that its review of, among other things, the aforementioned items, provided a reasonable basis for the issuance of the July 21, 2004 fairness opinion, recognizing that The Bank Advisory Group issued informed professional opinions – not certifications of value. Therefore, based on these analyses, it is the opinion of The Bank Advisory Group that the consideration to be received by the shareholders of Lamar Bancshares, Inc. common stock is fair from a financial point of view.

Conversion of Lamar Bancshares, Inc. Common Stock

     On the date the merger becomes effective, each outstanding share of Lamar Bancshares, Inc. common stock will be converted into:

     (a) a number of shares of MidSouth Bancorp, Inc. common stock equal to $12,556,351 divided by $34, and further divided by the number of shares of Lamar Bancshares, Inc. common stock outstanding on the effective date of the merger; plus

     (b) $10,494,000 cash less (i) the cash amount paid to Lamar Bancshares, Inc. option holders for options cancelled on the closing date of the merger pursuant to the merger agreement (estimated to be approximately $1,246,694, grossed up to factor in a maximum federal income tax rate of 35% and a maximum Louisiana state tax rate of 6%) and (ii) the excess over $200,000 of Lamar Bancshares, Inc.’s legal, accounting and investment banking fees related to the transaction other than those incurred before March 31, 2004, and expensed on Lamar Bancshares, Inc.’s financial statements as of and for the period ending March 31, 2004, plus the amount paid to Lamar Bancshares, Inc. by option holders after the date of the merger agreement in order to exercise any options (estimated to be approximately $0), with the result being divided by the number of shares of Lamar Bancshares, Inc. common stock outstanding on the effective date of the merger.

     If on the closing date of the merger the average closing sales price of MidSouth Bancorp, Inc. common stock on the American Stock Exchange for the ten trading days ending the day before such closing date (“Average Price”) is less than $31.50 per share, MidSouth shall adjust the conversion rate by multiplying the conversion rate by 1.07937. If on the closing date the Average Price exceeds $36.50, the conversion rate shall be adjusted by multiplying the conversion rate by 0.93151. If the Average Price is below $29.00, Lamar Bancshares, Inc., may terminate the merger transaction.

     On the basis of information available as of the date of this proxy statement/prospectus, Lamar Bancshares, Inc., estimates that the cash portion of the merger consideration will be $                    , and that the Lamar common stock per cash consideration will be $                    . On the basis of the Average Price of MidSouth Bancorp, Inc., common stock for the period ended                     , 2004, which was $                    , the stock portion of the merger consideration would be                     shares of MidSouth Bancorp, Inc. common stock for each share of Lamar Bancshares, Inc. common stock. The actual stock conversion ratio will depend on the Average Price of MidSouth Bancorp, Inc., common stock for the 10 day period ending the day before the closing of the merger.

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     Instead of issuing any fractional shares of MidSouth Bancorp, Inc. common stock, each shareholder of Lamar Bancshares, Inc. who would otherwise be entitled to a fractional share will receive a cash payment, without interest, equal to the fraction multiplied by the Average Price of a share of MidSouth Bancorp, Inc. common stock.

Effective Date

     A merger agreement will be filed with the Secretaries of State of Louisiana and Texas as soon as practicable after shareholder and regulatory approvals of the merger are obtained and all other conditions to the completion of the merger have been satisfied or waived. The merger will be effective when that agreement has been filed with and recorded by these bodies.

Procedure for Exchanging Certificates

     On the effective date of the merger, each Lamar Bancshares, Inc. shareholder will cease to have any rights as a shareholder of Lamar Bancshares, Inc., and his or her sole rights will be to receive MidSouth Bancorp, Inc. common stock and cash into which his or her shares of Lamar Bancshares, Inc. common stock have been converted pursuant to the merger agreement, and cash for any fractional shares, except for any Lamar Bancshares, Inc. shareholder who exercises statutory dissenters’ rights.

     Promptly after consummation of the merger, a letter of transmittal, together with instructions for the exchange of certificates representing shares of Lamar Bancshares, Inc. common stock for certificates representing shares of MidSouth Bancorp, Inc. common stock and cash, will be mailed to each person who was a shareholder of record of Lamar Bancshares, Inc. on the effective date of the merger. Shareholders are requested not to send in their Lamar Bancshares, Inc. common stock certificates until they have received a letter of transmittal and further written instructions. MidSouth Bancorp, Inc. common stock certificates and cash payments will be sent as promptly as practicable after receipt of a properly completed letter of transmittal accompanied by the appropriate Lamar Bancshares, Inc. common stock certificates.

     MidSouth Bancorp, Inc., at its option, may decline to pay former shareholders of Lamar Bancshares, Inc. who become holders of MidSouth Bancorp, Inc. common stock pursuant to the merger any dividends or other distributions that may have become payable to holders of record of MidSouth Bancorp, Inc. common stock following the effective date until they have surrendered their certificates for Lamar Bancshares, Inc. common stock. Any dividends not paid after one year from the date they first became payable as a result of the delay of a Lamar Bancshares, Inc. shareholder in surrendering his or her certificates will revert in full ownership of such dividends to MidSouth Bancorp, Inc., and MidSouth Bancorp, Inc. will have no further obligation to pay such dividends.

Treatment of Lamar Bancshares, Inc. Stock Options

     Prior to the consummation of the merger, Lamar Bancshares, Inc. will accelerate the exercisability of all previously granted options not currently exercisable. Any Lamar Bancshares, Inc. options not exercised at the effective date of the merger will be cancelled, and holders of such cancelled Lamar options will receive from MidSouth on the day following the closing date of the merger in connection with the cancellation of their options on the closing the following: (a) a cash amount equal to the same consideration (in stock and cash) payable to Lamar shareholders pursuant to the merger agreement, less the exercise price for the cancelled options; plus (b) a cash amount equal to the amount of tax savings that may be realized by MidSouth attributable to the payment made pursuant to item (a) above in this sentence.

Conditions to the Merger

     The respective obligations of Lamar Bancshares, Inc. and MidSouth Bancorp, Inc. to complete the merger are subject to the satisfaction or waiver of the following conditions specified in the merger agreement:

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     There can be no assurance that the conditions to consummation of the merger will be satisfied or waived. The merger will become effective when the merger has been recorded by the Louisiana and Texas Secretaries of State as of the time of filing with these bodies. It is currently anticipated that the effective time of the merger will occur during the third quarter of 2004.

     In addition to Lamar Bancshares, Inc. shareholder approval, consummation of the Merger will require the filing of certain documents with the Texas Department of Banking (“TDB”) and the approval of the Board of Governors of the Federal Reserve System. MidSouth Bancorp, Inc. has filed the necessary documents with the TDB and has filed an application seeking the required approval, and MidSouth Bancorp, Inc. expects to receive such approval by August 31, 2004; however, there can be no assurance that the approval will be obtained by that time or at all.

     The obligations of the parties to consummate the merger are also subject to additional conditions that are customary for transactions of this type.

     The companies intend to complete the merger as soon as practicable after all of the conditions to the merger agreement have been met or waived; however, there can be no assurance that the conditions will be satisfied.

Conduct of Business Prior to the Effective Date

     Lamar Bancshares, Inc. has agreed that it will use its best efforts to preserve the possession and control of all of its assets (other than those permitted to be distributed to shareholders before consummation of the merger in accordance with the merger agreement or those consumed or disposed of for value in the ordinary course) and the goodwill of customers and others having business relations with it, and will do nothing knowingly to impair its ability to keep and preserve its business.

     Lamar Bancshares, Inc. has also agreed that it will conduct its business only in the ordinary course consistent with past practices. In addition, except as otherwise provided in the merger agreement, Lamar Bancshares, Inc. has agreed that it will not, whether or not in the ordinary course, without the prior consent of MidSouth Bancorp, Inc.’s chief executive officer or his designee:

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     In addition, both Lamar Bancshares, Inc. and MidSouth Bancorp, Inc. have agreed to cooperate with one another and use their best efforts to satisfy all requirements or law for, and all conditions in the merger agreement to, the consummation of the merger, and to effect the merger at the earliest practicable date.

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     Lamar Bancshares, Inc. has further agreed that it will not solicit, initiate, encourage or knowingly facilitate any inquiry or the making of any proposal relating to an acquisition transaction or a potential acquisition transaction involving it. Lamar Bancshares, Inc. will use its best efforts to inform promptly its directors, officers, key employees, agents, and other representatives of the foregoing prohibitions.

     Lamar Bancshares, Inc. and its Board of Directors may have discussions and negotiations and furnish information to another party in reference to an unsolicited written acquisition proposal if the Board of Directors determines in good faith, after receipt of advice from its outside counsel, that the proposal could result in a superior proposal. Prior to providing any information to the other party, Lamar Bancshares, Inc.’s Board of Directors must notify MidSouth Bancorp, Inc. of the proposal and receive an appropriate confidentiality agreement from the other party.

Regulatory Approvals

     Consummation of the merger is subject to prior receipt of all required approvals and consents of the merger by all applicable federal and state regulatory authorities.

     The merger is subject to the prior approval of the Federal Reserve Board under Section 18(c) of the Bank Merger Act, 12 U.S.C. § 1828(c). The Federal Reserve Board may not approve the merger if:

     In every case, the Federal Reserve Board is required to consider the financial and managerial resources and future prospects of the banks concerned and the convenience and needs of the communities to be served. Under the Community Reinvestment Act of 1977, the Federal Reserve Board also must take into account the record of performance of each bank in meeting the credit needs of the entire community, including low and moderate-income neighborhoods, served by each bank holding company and its subsidiaries. Applicable regulations require publication of notice of an application for approval of the merger and an opportunity for the public to comment on the application in writing and to request a hearing.

     Any transaction approved by the Federal Reserve Board may not be completed until 30 days after such approval, during which time the U.S. Department of Justice may challenge such transaction on antitrust grounds and seek divesture of certain assets and liabilities. With the approval of the Federal Reserve Board and the United States Department of Justice, the waiting period may be reduced to 15 days.

Representations and Warranties of the Parties

     Pursuant to the merger agreement, Lamar Bancshares, Inc. and MidSouth Bancorp, Inc. made certain customary representations and warranties relating to their respective companies, subsidiaries, businesses and matters related to the merger. The representations and warranties generally must remain accurate through the completion of the merger unless the fact or facts that caused a breach of a representation and warranty has not had or is not reasonably likely to have a material adverse effect on the party making the representation and warranty. See “Conditions to the Merger.”

Waiver, Amendment and Termination

     The parties may waive in writing any of the conditions to their respective obligations to consummate the merger, other than the receipt of necessary regulatory and shareholder approvals. The merger agreement, including all related agreements, may also be amended or modified at any time, before or after its approval by the shareholders of Lamar Bancshares, Inc., by mutual agreement, except that any amendment made after shareholder approval may

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not alter the amount or type of consideration into which Lamar Bancshares, Inc. common stock will be converted without the additional approval of shareholders.

     The merger agreement may be terminated at any time prior to the effective date by mutual consent, or by either of the companies:

     The board of directors of MidSouth Bancorp, Inc. may terminate the merger agreement if Lamar Bancshares’s board of directors resolves to withdraw, modify or change its recommendation to Lamar Bancshares’s shareholders of the merger agreement, or recommends any acquisition of Lamar Bancshares, Inc. other than the merger.

     If Lamar Bancshares, Inc.’s Board of Directors determines that another proposal is superior to the merger because it is more favorable to Lamar Bancshares, Inc.’s shareholders from a financial point of view than the proposed merger, it may terminate the merger agreement subject to MidSouth Bancorp, Inc.’s right of first refusal to submit a revised acquisition proposal on terms not less favorable to Lamar Bancshares, Inc. than the terms of the superior proposal. MidSouth Bancorp, Inc. will have the right to exercise its right of first refusal within five business days after receipt of notice of the superior proposal from Lamar Bancshares, Inc.

Effect of Termination

     If the merger agreement is terminated, it will become void and have no effect and the parties will be relieved of all obligations and liabilities, except that the following provisions of the agreement will survive:

Financial Interests of Lamar Bancshares, Inc.’s Directors and Executive Officers in the Merger

     You should be aware that the directors and executive officers of Lamar Bancshares, Inc. have financial interests in the merger that are somewhat different from the interests of Lamar Bancshares, Inc. shareholders

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generally. These interests may cause some of these persons to view the proposed transaction differently than you view it.

     Indemnification and Insurance. MidSouth Bancorp, Inc. has agreed to indemnify and hold harmless Lamar Bancshares, Inc. and its directors and officers against any claims, and any related losses, that arise out of or are based upon an untrue statement or omission of a material fact made in this proxy statement/prospectus or the registration statement. MidSouth Bancorp, Inc. will reimburse each such person promptly as incurred for legal and other expenses reasonably incurred in connection with investigating or defending any such claims; provided, that MidSouth Bancorp, Inc. will not be liable to the extent that any such claim arises out of or is based upon any such untrue statement or omission made in reliance on information furnished to MidSouth Bancorp, Inc. by Lamar Bancshares, Inc. or, with respect to any indemnified person, by that person.

     Acceleration of Exercisability of Options. Prior to the consummation of the merger, Lamar Bancshares, Inc. will accelerate the exercisability of all previously granted Lamar Bancshares, Inc. stock options. Any options not exercised at the effective date of the merger will be cancelled, and the holders of such cancelled options will receive from MidSouth Bancorp, Inc., the consideration set forth in the merger agreement. See “The Merger Agreement – Treatment of Lamar Bancshares, Inc. Stock Options.”

     Employment Agreements. At closing, MidSouth Bancorp, Inc. will enter into employment agreements with Lonnie Weir, Ron Reed, Tim Zajonc, Travis Riley, David McCrady, Wilma Pace, Linda Ott Reed, Jason Riley, Carole Malmberg, Linda Allen and David Locke, officers and, in the cases of Messrs. Weir and Reed, directors of the Bank. . The agreement with Mr. Weir will have a one-year term beginning on the effective date of the merger, provide for an annual salary of $134,013, and under certain circumstances would restrict him from competing with MidSouth Bancorp, Inc. for one year after termination; the agreement would be followed by a consulting agreement as agreed upon by MidSouth Bancorp, Inc

     The agreement with Ron Reed will have a term beginning on the effective date of the merger and ending five years later, subject to renewal, will provide for an annual salary of $140,000, plus additional potential performance bonuses, and under certain circumstances would restrict Mr. Reed from competing with MidSouth Bancorp, Inc. for two years in the Counties of Jefferson, Brazos, and Montgomery if his employment were to terminate during this period.

     The other agreements will have a one-year term beginning on the closing date of the merger, provide for an annual salary ranging from $31,000 to $90,000 and under certain circumstances would restrict each employee from competing with MidSouth Bancorp, Inc. for one year if his employment were to terminate during this period.

     MidSouth Bancorp, Inc., Board of Directors. MidSouth Bancorp, Inc. will cause to be appointed to its board of directors, to take office immediately after the effective date of the merger, the following persons for the following terms: Lonnie Weir for a term ending at MidSouth, Inc.,’s 2005 annual stockholders meeting, Ron Reed for a term ending at MidSouth’s 2006 annual stockholders meeting, and Joe Tortorice, Jr. for a term ending at MidSouth’s 2007 annual stockholders meeting.

Expenses

     The merger agreement provides generally that expenses incurred in connection with the merger agreement and the transactions contemplated thereby will be borne by the party that has incurred them.

Accounting Treatment

     MidSouth Bancorp, Inc. will account for the merger using the purchase method of accounting. Under this accounting method, MidSouth Bancorp, Inc. would record the acquired identifiable assets and liabilities assumed at their fair market value at the time the merger is complete. Any excess of the cost of Lamar Bancshares, Inc. over the sum of the fair values of tangible and identifiable intangible assets less liabilities assumed would be recorded as goodwill. Based on information as of March 31, 2004, management of MidSouth Bancorp, Inc. estimates that the total merger consideration (including issuance of common stock and payments for cancelled stock options) will be approximately $23 million. Using information as of March 31, 2004, estimated goodwill and other intangibles would total approximately $10 million. MidSouth Bancorp, Inc.’s reported income would include the operations of

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Lamar Bancshares, Inc. after the merger. Financial statements of MidSouth Bancorp, Inc. after completion of the merger would reflect the impact of the merger with Lamar Bancshares, Inc. Financial statements of MidSouth Bancorp, Inc. issued before completion of the merger would not be restated retroactively to reflect Lamar Bancshares, Inc.’s historical financial position or results of operation.

Status Under Federal Securities Laws; Restrictions on Resales

     The shares of MidSouth Bancorp, Inc. common stock to be issued pursuant to the merger agreement have been registered under the Securities Act of 1933, allowing those shares to be freely traded without restriction by persons who will not be “affiliates” of MidSouth Bancorp, Inc. or who were not “affiliates” of Lamar Bancshares, as that term is defined in Rule 405 under the Securities Act of 1933.

     Directors and certain officers of Lamar Bancshares, Inc. may be deemed to be “affiliates” of Lamar Bancshares, Inc. These people will not be able to resell the MidSouth Bancorp, Inc. common stock received by them unless such stock is registered for resale under the Securities Act of 1933 or an exemption from the registration requirements of the Securities Act of 1933 is available. All affiliates are required under federal securities laws not to sell shares of MidSouth Bancorp, Inc. common stock received by them in violation of the Securities Act of 1933 and the rules and regulations thereunder.

MATERIAL FEDERAL INCOME TAX CONSEQUENCES

     The following is a summary of the material federal income tax consequences to holders of Lamar Bancshares, Inc. common stock resulting from the merger. The following is based upon applicable federal law and judicial and administrative interpretations on the date hereof, any of which is subject to change at any time.

     This discussion assumes that you hold your shares of Lamar Bancshares, Inc. common stock as capital assets and does not address the state tax consequences or the consequences that may be relevant if you receive special treatment under some United States federal income tax laws. Shareholders receiving this special treatment include but are not limited to:

Treatment of Merger

     (a) The merger qualifies as a reorganization under Section 368(a)(1)(A) of the Internal Revenue Code, and Lamar Bancshares, Inc. and MidSouth Bancorp, Inc. each will be a “party to a reorganization” within the meaning of Section 368(b) of the Code.

     (b) No gain or loss will be recognized by Lamar Bancshares, Inc. or MidSouth Bancorp, Inc., as a result of the merger.

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     (c) A shareholder of Lamar Bancshares, Inc. who receives both MidSouth Bancorp, Inc. common stock and cash consideration in exchange for all of his or her shares of Lamar Bancshares, Inc. common stock generally will recognize gain, but not loss, to the extent of the lesser of:

     (1) the excess, if any, of:

     (a) the sum of the aggregate fair market value of the cash and MidSouth Bancorp, Inc. common stock received, over

     (b) the shareholder’s tax basis in Lamar Bancshares, Inc. common stock; and

     (2) the amount of cash received;

     (d) The aggregated tax basis of the MidSouth Bancorp, Inc. common stock received by shareholders of Lamar Bancshares, Inc. who exchange all of their Lamar Bancshares, Inc. common stock in the merger will equal such shareholder’s aggregate tax basis in the shares of Lamar Bancshares, Inc. common stock being exchanged, reduced by any amount allocable to a fractioned share interest of MidSouth Bancorp, Inc. common stock for which cash is received and by the amount of any cash consideration received, and increased by the amount of taxable gain, if any recognized by such shareholder in the merger.

     (e) The holding period of the shares of MidSouth Bancorp, Inc. common stock received in the merger will include the period during which the shares of Lamar Bancshares, Inc. common stock surrendered in exchange therefor were held, provided such shares of Lamar Bancshares, Inc. common stock were held as capital assets at the effective time of the merger.

     On April 30, 2004, the Internal Revenue Service issued proposed treasury regulations that would permit a stockholder that acquired different blocks of Lamar Bancshares, Inc. common stock at different times and at different prices to determine their tax basis and holding period of the shares of MidSouth Bancorp, Inc. common stock they receive in the merger separately with reference to each block of Lamar Bancshares, Inc. common stock exchanged therefore.

     If you acquired different blocks of Lamar Bancshares, Inc. common stock at different times and at different prices, you will be provided the option to specify, by certificate number, which shares of Lamar Bancshares, Inc. common stock that will be treated as exchanged for the shares of MidSouth Bancorp, Inc. common stock that you receive and which shares of Lamar Bancshares, Inc. common stock that will be treated as exchanged for the cash that you receive, subject to the right of MidSouth Bancorp, Inc. to limit the total amount of shares of MidSouth Bancorp, Inc. common stock and cash you will receive for your shares of Lamar Bancshares, Inc. common stock. Remaining blocks of Lamar Bancshares, Inc. common stock not specifically allocated by you to cash or to MidSouth Bancorp, Inc. common stock will be allocated pro rata between the remaining amount of MidSouth Bancorp, Inc. common stock and cash that you receive in exchange for your shares of Lamar Bancshares, Inc. common stock. You are urged to consult with your tax advisor with respect to whether you should specify which of your shares of Lamar Bancshares, Inc. common stock are exchanged for MidSouth Bancorp, Inc. common stock and which are exchanged for cash, and with respect to the possible application of the proposed regulations to you in your particular circumstances.

Dissenters

     A holder of Lamar Bancshares, Inc. common stock who exercises dissenters’ rights in connection with the merger generally will recognize capital gain or loss (assuming the common stock is held as a capital asset) equal to the difference, if any, between the dissenting holder’s tax basis in the Lamar Bancshares, Inc. common stock exchanged and the amount of cash received in exchange therefor.

Possible Treatment of Gain as a Dividend

     If the cash you receive in the merger has the effect of the distribution of a dividend for United States federal income tax purposes, the gain you recognize generally will be treated as dividend income. If you are an

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individual, your dividend income generally will be subject to tax at long-term capital gains rates, provided that certain holding period and other requirements are satisfied.

     For purposes of determining whether any gain recognized in the merger will be treated as capital gain or dividend income, if you exchange your Lamar Bancshares, Inc. common stock for a combination of MidSouth Bancorp, Inc. common stock and cash, then you will be treated as if you first exchanged all of your shares of Lamar Bancshares, Inc. common stock solely for MidSouth Bancorp, Inc. common stock and then MidSouth Bancorp, Inc. immediately redeemed a portion of that common stock in exchange for the cash that you actually received. Gain recognized in this deemed redemption will be treated as capital gain if the deemed redemption results in a “meaningful reduction” in your deemed percentage stock ownership in MidSouth Bancorp, Inc. For this purpose, your stock ownership will include stock that you own constructively under Section 318 of the Code. The Internal Revenue Service has ruled that a shareholder in a publicly held corporation whose relative stock interest is minimal and who exercises no control over corporate affairs is generally treated as having had a “meaningful reduction” if his or her percentage stock ownership in the corporation has been reduced to any extent, taking into account the shareholder’s actual and constructive ownership before and after the deemed redemption. Accordingly, in most circumstances, gain you recognize if you exchange your shares of Lamar Bancshares, Inc. common stock for a combination of MidSouth Bancorp, Inc. common stock and cash will be capital gain.

Tax Basis and Holding Period

     Your tax basis in the MidSouth Bancorp, Inc. common stock received in the merger will equal your tax basis in the Lamar Bancshares, Inc. common stock surrendered in the merger, increased by the amount of taxable gain or dividend income, if any, recognized in the merger, and decreased by the amount of cash, if any, received in the merger (excluding any cash received in lieu of a fractional share interest). Your holding period in the shares of MidSouth Bancorp, Inc. common stock received in the merger generally will include your holding period for the shares of Lamar Bancshares, Inc. common stock exchanged therefore. If you have differing bases of holding periods in respect of your shares of Lamar Bancshares, Inc. common stock, you should consult your tax advisor prior to the exchange with regard to identifying the bases or holding periods of the particular shares of MidSouth Bancorp, Inc. common stock received in the merger.

Cash Received in Lieu of Fractional Shares

     If you receive cash in lieu of a fractional share of MidSouth Bancorp, Inc. common stock, you will recognize capital gain or loss equal to the difference between the amount of cash you receive and the portion of your tax basis allocable to the fractional share. Such gain or loss will be long-term capital gain or loss for United States federal income tax if you have held your shares of Lamar Bancshares, Inc. common stock for more than one year at the time the merger is completed. Long-term capital gain of an individual is generally subject to a maximum United States federal income tax rate of 15%.

Backup Withholding

     Unless you comply with certain reporting or certification procedures or are an “exempt recipient” (in general, corporations and certain other entities), your may be subject to a backup withholding tax of 28% with respect to any cash payments received in the merger. Foreign shareholders should consult their tax advisors with respect to the application of withholding rules to any cash payments received in the merger.

Reporting Requirements

     If you receive any shares of MidSouth Bancorp, Inc. common stock pursuant to the merger, you will be required under Section 1.368-3 of the Treasury Regulations to attach to your federal income tax return for the taxable year in which the merger occurs, a complete statement of all facts pertinent to the non-recognition of any gain or loss in the merger. This statement should include a statement as to your cost or other tax basis of the Lamar Bancshares, Inc. common stock you exchanged in the merger, and the amount of the cash and a description of the shares of MidSouth Bancorp, Inc. common stock you received in exchange for your shares of Lamar Bancshares, Inc. common stock pursuant to the merger. You should consult your tax advisor regarding the disclosure requirements and how they apply to you in your particular circumstances.

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     AS A RESULT OF THE COMPLEXITY OF THE TAX LAWS, AND BECAUSE THE TAX CONSEQUENCES TO ANY PARTICULAR SHAREHOLDER MAY BE AFFECTED BY MATTERS NOT DISCUSSED HEREIN, WE RECOMMEND THAT YOU CONSULT YOUR PERSONAL TAX ADVISOR CONCERNING THE APPLICABLE FEDERAL, STATE AND LOCAL INCOME TAX CONSEQUENCES OF THE MERGER TO YOU.

DISSENTERS’ RIGHTS

     If you were a stockholder of Lamar Bancshares, Inc. as of the record date, you may exercise dissenters’ rights in connection with the merger by complying with Articles 5.11, 5.12 and 5.13 of the Texas Business Corporation Act.

     By exercising dissenters’ rights, you will be entitled to receive, if the merger is completed, the “fair value” of your shares of Lamar Bancshares, Inc. common stock as of the day immediately prior to the date of the meeting. As defined by Texas law, “fair value” excludes any appreciation or depreciation in anticipation of the proposed merger. This value may differ from the value of the consideration that you would otherwise receive in the merger. The following is a summary of the statutory procedures that you must follow if you elect to exercise your dissenters’ rights under the Texas Business Corporation Act. This summary is not complete and is qualified in its entirety by reference to Articles 5.11, 5.12 and 5.13 of the Texas Business Corporation Act.

     How to exercise and perfect your right to dissent. In order to be eligible to exercise your right to dissent from the merger and to receive, upon compliance with the statutory requirements summarized below, the fair value of your shares of Lamar Bancshares, Inc. common stock as of the day immediately preceding the meeting, excluding any appreciation or depreciation in anticipation of the merger, you must:

     In order to exercise properly your dissenters’ rights, you must refrain from voting by proxy or in person in favor of the merger agreement. A stockholder who signs and returns an unmarked proxy card will have his or her shares voted “FOR” the merger agreement and, as a consequence of that action, such stockholder will be foreclosed from exercising rights as a dissenting stockholder.

     Your demand for payment. If you comply with the items described above and the merger is completed, MidSouth Bancorp, Inc. will within 10 days of the completion of the merger deliver or mail to all holders of Lamar Bancshares, Inc. common stock who satisfied the above requirements a written notice that the merger has been completed. You must, within 10 days of the date the notice was sent to you by MidSouth Bancorp, Inc., send a written demand to MidSouth Bancorp, Inc. for payment of the fair value of your shares of Lamar Bancshares, Inc. common stock. Such written demand must state the number of the shares that you owned as of the record date and your estimate of the fair value of the shares. The fair value of your shares of Lamar Bancshares, Inc. common stock will be the value of the shares on the day immediately preceding the meeting, without regard to any appreciation or depreciation in anticipation of the merger.

     Lamar Bancshares, Inc. Shareholders considering seeking appraisal should be aware that the fair value of their shares as determined under Texas law could be more than, the same as, or less than the merger consideration they would be entitled to receive pursuant to the merger agreement if they did not seek appraisal of their shares. Shareholders also should be aware that investment banking opinions as to fairness from a financial point of view are not necessarily opinions as to fair value under the Texas Business Corporation Act.

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     If you should fail to make such a demand within the 10 day period, you will lose the right to dissent and will be bound by the terms of the merger agreement. In order to present your dissenters’ rights, you must also submit your stock certificates to MidSouth Bancorp, Inc. within 20 days of making a demand for payment with a notation on your stock certificates that such demand has been made. The failure to do so will, at MidSouth Bancorp, Inc.’s option, terminate your rights to dissent and appraisal unless a court of competent jurisdiction for good and sufficient cause shown directs otherwise. Any notice addressed to MidSouth Bancorp, Inc. must be addressed to:

MidSouth Bancorp, Inc.
Attn: Corporate Secretary
102 Versailles Boulevard
Lafayette, Louisiana 70501

     Shareholders who hold their shares in brokerage accounts or other nominee forms and who wish to exercise appraisal rights are urged to consult with their broker to determine appropriate procedures for the making of a demand for appraisal by such nominee.

     MidSouth Bancorp, Inc.’s action upon receipt of your demand for payment. Within 20 days of receiving your written demand for payment and estimate of the fair value of your shares of Lamar Bancshares, Inc. common stock. MidSouth Bancorp, Inc. must mail or deliver to you a written notice that either:

     Payment of the fair value of your shares of Lamar Bancshares, Inc. common stock upon agreement of an estimate. If you and MidSouth Bancorp, Inc. agree upon the fair value of your shares of Lamar Bancshares, Inc. common stock within 60 days after completion of the merger, MidSouth Bancorp, Inc. will pay the amount of the agreed value to you upon receipt of your duly endorsed share certificates within 90 days of the completion of the merger. Upon payment of the agreed fair value, you will cease to have any interest in such shares.

     Commencement of legal proceedings if a demand for payment remains unsettled. If you and MidSouth Bancorp, Inc. have not agreed upon the fair value of your shares of Lamar Bancshares, Inc. common stock within the 60-day period immediately subsequent to the completion of the merger, then either you or MidSouth Bancorp, Inc. may, within 60 days of the expiration of the 60-day period after the effective time of the merger, file a petition in any court of competent jurisdiction in Beaumont, Texas, asking for a finding and determination of the fair value of the shares. If filed by a stockholder, service of the petition must be made upon MidSouth Bancorp, Inc. as the surviving corporation, and MidSouth Bancorp, Inc. must, within 10 days after service, file with the clerk of the court a list with the names and addresses of all stockholders who have demanded payment and not reached agreement as to the fair value. If filed by MidSouth Bancorp, Inc., the petition must be accompanied by such a list. The clerk of court is to give notice to MidSouth Bancorp, Inc. and all stockholders named on the list of the time and place fixed for the hearing of the petition. After the hearing of the petition, the court will determine the stockholders who have complied with the statutory requirements and have become entitled to the valuation of and payment for their shares, and the court will appoint one or more qualified appraisers to determine the fair value.

     The appraisers may examine the books and records of Lamar Bancshares, Inc. and will provide interested parties a reasonable opportunity to submit pertinent evidence. The appraisers will make a determination of the fair value upon such examination as they deem proper. The appraisers will file a report of the value in the office of the clerk of court, notice of which will be given to the parties in interest. The parties in interest may submit exceptions to the report, which will be heard before the court upon the law and the facts. The court will adjudge the fair value of the shares of the stockholders entitled to payment for their shares and will direct the payment thereof by MidSouth Bancorp, Inc., as the surviving corporation, together with interest, which will begin to accrue 91 days

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after the effective time of the merger. However, the judgment will be payable only upon and simultaneously with surrender of the certificates representing your shares, duly endorsed. Upon MidSouth Bancorp, Inc.’s payment of the judgment, you will cease to have any interest in the shares. The court will allow the appraisers a reasonable fee as court costs, and all court costs will be allotted between the parties in the manner that the court determines to be fair and equitable, with the respective parties to bear their own attorneys’ fees. Any shareholder who had demanded payment for such holder’s shares may withdraw such demand at any time before payment or before any petition has been filed for valuation by the court. After a demand has been withdrawn, the shareholder and all persons claiming under the stockholder will be conclusively presumed to have approved the merger agreement and will be bound by its terms.

     Failure to follow the steps required by Articles 5.11, 5.12 and 5.13 of the Texas Business Corporation Act for perfecting appraisal rights may result in the loss of appraisal rights, in which event a Lamar Bancshares, Inc. shareholder will be entitled to receive the consideration with respect to his, her or its dissenting shares in accordance with the merger agreement. In view of the complexity of the provisions of Articles 5.11, 5.12 and 5.13 of the Texas Business Corporation Act, if you are a Lamar Bancshares, Inc. shareholder and are considering exercising your appraisal rights under the Texas Business Corporation Act, you should consult your own legal advisor.

     INFORMATION ABOUT LAMAR BANK AND LAMAR BANCSHARES, INC.

     Lamar Bank was organized by local Beaumont, Texas businessmen who recognized a need for banking facilities in south Beaumont, and it opened for business in August 1959. The past president of First National Bank of Beaumont, Paul Tullos, was named as the first president of Lamar Bank. Richard Cobb succeeded Tullos in 1962. In 1966, Lonnie Weir was elected as president and CEO of Lamar Bank, was later named Chairman of the Board in 1986, and still serves as Chairman of the Board today. Ron Reed was elected President of Lamar Bank in 1999, and was elected to the position of CEO in 2001.

     Lamar Bancshares, Inc. was formed in 1983, and Lamar Bank’s name was changed from Lamar State Bank to Lamar Bank. Lamar Bank currently has three full service locations in Beaumont, Texas, one in Vidor, Texas, and recently opened branches in College Station, Texas in November 2001 and Conroe, Texas in May 2002. In 1996, the home office designation for Lamar Bank and Lamar Bancshares, Inc. officially became 555 N. Dowlen Road, Beaumont, Texas 77706.

     Lamar Delaware Financial Corporation, a Delaware corporation, was founded on March 25, 1992. Other than owning 100% of the stock of Lamar Bank, Lamar Delaware Financial Corporation conducts no activities.

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BENEFICIAL OWNERSHIP OF LAMAR BANCSHARES, INC. COMMON STOCK

     The following table sets forth certain information regarding the beneficial ownership of Lamar Bancshares, Inc.’s common stock as of June 18, 2004, by (i) each person known by Lamar Bancshares, Inc. to be the beneficial owner of more than 5% of the outstanding shares of common stock of Lamar Bancshares, Inc.; (ii) each director of Lamar Bancshares, Inc.; and (iii) all directors and executive officers of Lamar Bancshares, Inc., as a group.

Lamar Bancshares, Inc. – Directors and Insiders Beneficial Stock Ownership
June 18, 2004