EXHIBIT 4.6

             AMENDMENT TO CULLEN/FROST BANKERS, INC. 1992 STOCK PLAN


         The Board of Directors of Cullen/Frost Bankers, Inc., pursuant to
Section 9.5 of Cullen/Frost Bankers, Inc. 1992 Stock Plan (the "Plan"), hereby
amends the Plan as described below; provided, however, that such amendments
shall become effective only after approval by the Company's shareholders. The
amendments are as follows:

The following terms and accompanying definitions shall be added to the Plan
under Section 2.1:

         (r)  "Covered Employee" means a Participant who the Committee
              determines is likely to be, as of the date of vesting and/or
              payout of Incentive, as applicable, is one of the group of
              "covered employees," as defined in the regulations promulgated
              under Code Section 162(m), or any successor thereto.

         (s)  "Performance-Based Exception" means the performance-based
              exception from the tax deductibility limitations of Code Section
              162(m).

Section 5.1 of the Plan shall be deleted and replaced with the following:

5.1      NUMBER OF SHARES AVAILABLE FOR GRANT. Subject to adjustment as provided
         in Section 5.2 herein, the number of Shares hereby reserved for
         issuance to Participants under the Plan shall be two million eight
         hundred sixty thousand (2,860,000). In no event may greater than two
         hundred sixty-five thousand (265,000) shares be available for issuance
         with respect to grants of Restricted Stock under the Plan. The Board
         shall determine the appropriate methodology for calculating the number
         of Shares issued pursuant to the Plan. Unless and until the Board
         determines that an Incentive shall not be designed to comply with the
         Performance-Based Exception, the following rules shall apply to grants
         of such Incentives under the Plan:

         (a)  Stock Options: The maximum aggregate number of shares of Common
              Stock that may be granted in the form of Stock Options, pursuant
              to any Incentives granted in any one fiscal year to any one single
              Participant, shall be four hundred thousand (400,000).

         (b)  SARs: The maximum aggregate number of shares of Common Stock that
              may be granted in the form of Stock Appreciation Rights, pursuant
              to any Incentives granted in any one fiscal year to any one single
              Participant, shall be four hundred thousand (400,000).


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         (c)  Restricted Stock: The maximum aggregate grant with respect to
              Incentives granted in the form of Restricted Stock granted in any
              one fiscal year to any one participant shall be one hundred fifty
              thousand (150,000) shares of common stock.

Section 5.4 shall be added to the Plan and shall read as follows:

5.4      PERFORMANCE MEASURES. Unless and until the Committee proposes for
         shareholder vote and shareholders approve a change in the general
         performance measures set forth in this Section 5.4, the attainment of
         which may determine the degree of payout and/or vesting with respect to
         Incentives granted to Covered Employees which are designed to qualify
         for the Performance-Based Exception, the performance measure(s) to be
         used for purposes of such grants shall be chosen from among:

         (a)  Return on Equity;

         (b)  Earnings Per Share;

         (c)  Operating Cash Flow;

         (d)  Gross Revenue;

         (e)  Income Before Taxes;

         (f)  Net Income;

         (g)  Return on Revenue; and

         (h)  Stock Price Appreciation.

         The Committee shall have the discretion to adjust the determinations of
         the degree of attainment of the preestablished performance goals,
         provided, however, that Incentives which are designed to qualify for
         the Performance-Based Exception, and which are held by Covered
         Employees, may not be adjusted upward (the Committee shall retain the
         discretion to adjust such Incentives downward).

         In the event that applicable tax and/or securities laws change to
         permit Board discretion to alter the governing performance measures
         without obtaining shareholder approval of such changes, the Board shall
         have sole discretion to make such changes without obtaining shareholder
         approval. In addition, in the event that the Committee determines that
         it is advisable to grant Incentives which shall not qualify for the
         Performance-Based Exception, the Committee may make such grants without
         satisfying the requirements of Code Section 162(m).


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The second sentence of Section 7.2 of the Plan shall be deleted and replaced
with the following:

         Each Incentive Stock Option and all rights granted thereunder shall not
         be transferable other than by will or the laws of descent and
         distribution, and shall be exercisable during the optionee's lifetime
         only by the optionee or his guardian or legal representative. Except as
         may be otherwise provided by the Committee, each Nonqualified Stock
         Option and all rights granted thereunder shall not be transferable
         other than by will or the laws of descent and distribution, and shall
         be exercisable during the optionee's lifetime only by the optionee or
         his guardian or legal representative.

Section 9.7 shall be added to the Plan and shall read as follows:

9.7      POOLING OF INTERESTS ACCOUNTING. Notwithstanding any other provision of
         the Plan to the contrary, in the event that the consummation of a
         Change in Control is contingent on using the pooling of interests
         accounting methodology, the Board may take any action necessary to
         preserve the use of pooling of interests accounting.

Section 9.8 shall be added to the Plan and shall read as follows:

9.8      COMPLIANCE WITH CODE SECTION 162(m). At all times when Code Section
         162(m) is applicable, all Incentives granted under this Plan shall
         comply with the requirements of Code Section 162(m); provided, however,
         that in the event the Board determines that such compliance is not
         desired with respect to any Incentive or Incentives available for grant
         under the Plan, then compliance with Code Section 162(m) will not be
         required. In addition, in the event that changes are made to Code
         Section 162(m) to permit greater flexibility with respect to any
         Incentive or Incentives available under the Plan, the Board may make
         any adjustments it deems appropriate.