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                           InVitro International

                          STOCK OPTION AGREEMENT
          UNDER 1996 STOCK OPTION PLAN FOR NON-EMPLOYEE DIRECTORS
                  ______________________________________


                                              Date of Grant:  October 1, 1996


  INVITRO INTERNATIONAL, a California corporation (the "Company") hereby
grants to WILLIAM M. CURTIS ("Optionee"), pursuant to the 1996 Stock Option
Plan for Non-Employee Directors of the Company (the "Plan"), a copy of which
is appended hereto and made a part hereof as Schedule I, an option to purchase
a total of TWENTY-FIVE THOUSAND (25,000) shares of Common Stock of the Company
at a price of ONE DOLLAR ($1.00) per share (subject to adjustment as provided
in Section 8 of the Plan), on the terms and conditions set forth in the Plan
and hereinafter.  This option shall not be exercisable later than on October
1, 2006 (herein referred to as the "Expiration Date"), and may only be
exercised at a time when the Optionee is an employee of the Company except as
otherwise provided in paragraphs 6(d) and 6(e) of the Plan in the event of
termination of service as a director of the Company.

  1.    Vesting.  Subject to the terms and conditions of this Agreement,
the shares subject this option shall be exercisable as follows:

(a)     The first EIGHT THOUSAND THREE HUNDRED THIRTY-THREE (8,333) shares
        covered by this option may be exercised at any time, in whole or in
        part, from and after OCTOBER 1, 1997; and

(b)     The next EIGHT THOUSAND THREE HUNDRED THIRTY-THREE (8,333) shares
        covered by this option may be exercised at any time, in whole or in
        part, from and after OCTOBER 1, 1998; and 

(c)     The remaining EIGHT THOUSAND THREE HUNDRED THIRTY-FOUR (8,334) shares
        covered by this option may be exercised at any time, in whole or in
        part, from and after OCTOBER 1, 1999;

provided, however, that in no event shall this option be exercisable later
than the Expiration Date.

  2.    Termination.  This option and all rights hereunder to the extent
such rights shall not have been exercised shall terminate and become null and
void if the Optionee ceases to be a director of the Company (whether by
resignation, retirement, dismissal, death or otherwise), except that (a) in
the event of the mandatory retirement pursuant to Board policy, death or
permanent disability of the Optionee while











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a director of the Company, this option may be exercised within the applicable
period of time and by the persons indicated in paragraph 6(e) of the Plan, and
(b) in the event of the termination of the Optionee's service as a director of
the Company for any other reason, this option only to the extent exercisable
at the date of such termination may be exercised prior to the expiration of
three (3) months from the date of such termination, and shall terminate in all
other respects; provided, however, that in no event may this option be
exercised after the Expiration Date.

  3.    Exercise.  This option is exercisable with respect to all, or from
time to time with respect to any portion, of the shares then subject to such
exercise, by delivering written notice of such exercise, in the form
prescribed by the Stock Option Committee, to the principal office of the
Secretary of the Company.  Each such notice shall be accompanied by payment in
full of the purchase price of such shares.

  4.    Non-Transferable.  This option shall during the Optionee's
lifetime be exercisable only by the Optionee, and neither it nor any right
thereunder shall be transferable except by will or laws of descent and
distribution, or be subject to attachment, execution or other similar process. 
In the event of any attempt by the Optionee to alienate, assign, pledge,
hypothecate or otherwise dispose of the option or any right thereunder, except
as provided for herein, or in the event of the levy of any attachment,
execution or similar process upon the rights or interest hereby conferred, the
Company may terminate the option by notice to the Optionee and the option
shall thereupon become null and void.

  5.    Miscellaneous.

  (a)   Neither the granting of this option nor the exercise thereof shall
be construed as conferring upon the Optionee any right to continue as a
director of the Company, or as interfering with or restricting in any way the
right of the Company to terminate such services at any time in accordance with
applicable law.

  (b)   Neither the Optionee, nor any person entitled to exercise his or
her rights in the event of his or her death, shall have any of the rights of a
shareholder with respect to the shares subject to the option, except to the
extent that certificates for such shares shall have been issued upon exercise
of the option as provided for herein.

  (c)   The Company is relieved from any liability for the non-issuance or
non-transfer or any delay in the issuance or transfer of any shares of Common
Stock subject to this option which results from the inability of the Company
to obtain, or in any delay in obtaining, from each regulatory body having
jurisdiction all requisite authority to issue or transfer shares of Common
Stock of the Company in satisfaction of this option if counsel for the Company
deems such authority necessary for the lawful issuance or transfer of any such
shares.

  (d)   No Common Stock acquired by exercise of this option shall be sold
or otherwise disposed of in violation of any federal or state securities law
or regulation.

  (e)   This option shall be exercised in accordance with such administra-
tive regulations as the Stock Option Committee may from time to time adopt. 
All decisions of the Stock Option Committee upon any question arising under
the Plan or under this instrument shall be conclusive and binding upon the
Optionee and all other persons.



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  IN WITNESS WHEREOF, this Stock Option Agreement has been executed as of
the day and year first written above.

                               INVITRO INTERNATIONAL

                               By:  /s/  W. Richard Ulmer
                                    -----------------------                    
                                    W. RICHARD ULMER, President                
             
[Corporate Seal]

ATTEST:

/s/  Dennnis E. Chenoweth
------------------------------------------
Dennis E. Chenoweth, Senior Vice President












































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