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     EXHIBIT "A" incorporated herein by reference. The Executive shall provide
     such services in compliance with the requests of the Company's Board of
     Directors, and the Executive shall report the progress of his efforts to
     the Board of Directors on a regular basis. Executive shall perform the
     services at Zapata's One Riverway offices or such other location(s) as the
     Company may reasonably designate, and he shall be an independent consultant
     and shall not be deemed for any purpose to be an employee, agent or servant
     of the Company or Zapata Protein. The Company shall have no direction or
     control of the Executive except in the results to be obtained.

2.   Direct Compensation:  As compensation for services rendered hereunder, the
     Company shall pay the Executive the amounts due pursuant to Paragraph 5.B
     of the Employment Agreement commencing on July 15, 1994, in a monthly
     amount equal to Fourteen Thousand Five Hundred Eighty-Three and 33/100
     Dollars ($14,583.33), until the earlier of: (a) January 15, 1995 or (b) the
     sale of all or substantially all of the capital stock or assets of Zapata
     Protein.

     If the event in subparagraph 2(a) of this Agreement occurs first, the
     Company shall pay any remaining amounts owed under Paragraph 5.B of the
     Employment Agreement at the rate of Three Hundred Fifty-Eight Thousand Six
     Hundred and No/100 Dollars ($358,600.00) per year until the full amount to
     which the Executive is entitled under Paragraph 5.B of the Employment
     Agreement is paid to the Executive.

     If the event in subparagraph 2(b) of this Agreement occurs first, the
     Company shall assign all of its rights and obligations under this Agreement
     to Zapata Protein and/or its successor; provided, however, that if all or
     substantially all of the capital stock or assets of Zapata Protein are sold
     to a party with which the Executive has no relationship or interest of any
     kind, including, but not limited to, a relationship or interest as an
     investor, stockholder, officer or consultant, then the Company shall remain
     liable for all remaining amounts payable to the Executive pursuant to
     Paragraph 2(c) of this Agreement.  Subject to the foregoing, the Executive
     and Zapata Protein hereby consent to any such assignment pursuant to this
     Agreement, and Zapata Protein agrees to pay or cause to be paid all
     remaining amounts due to the Executive under Paragraph 5.B of the
     Employment Agreement in the event of such assignment at a rate of One
     Hundred Seventy-Five Thousand and No/100 Dollars ($175,000.00) per year
     until the full amount to which the Executive is entitled under Paragraph
     5.B of the Employment Agreement is paid to the Executive.

     In no event shall the amounts payable hereunder pursuant to Paragraph 5.B
     of the Employment Agreement be less than or exceed the total amount due
     under Paragraph 5.B of the Employment Agreement as of July 15, 1994.

3.   Reimbursement of Expenses:  The Company shall reimburse the Executive for
     all reasonable and necessary expenses he incurs under this Agreement.  The
     Company shall provide the Executive office space at One Riverway, Houston,
     Texas 77056 (or at such other location(s) as the Company may reasonably
     designate) and one reserved parking space for the duration

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