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                                                                EXHIBIT 10.67(D)

                            SEVENTH AMENDMENT TO THE
                                CREDIT AGREEMENT


         This SEVENTH AMENDMENT TO THE CREDIT AGREEMENT (this "Amendment") is
dated as of September 30, 1996 and entered into by and among Collagen
Corporation, a Delaware corporation (the "Borrower"), and The Bank of New York
(the "Bank"), and is made with reference to that certain Credit Agreement dated
as of November 15, 1994, by and among the Borrower and the Bank, as amended (the
"Credit Agreement"). Capitalized terms used herein without definition shall have
the same meanings herein as set forth in the Credit Agreement.

                                    RECITALS

         WHEREAS, the Borrower and the Bank desire to amend the Credit Agreement
to suspend the application of certain of the financial covenants set forth
therein for the fiscal quarter of the Borrower ending September 30, 1996; and

         WHEREAS, the Bank is willing to agree to the requested amendments,
subject to the terms of this Amendment.

         NOW, THEREFORE, in consideration of the foregoing and the mutual
covenants and agreements set forth herein, the parties hereto agree as follows:

         SECTION 1.   AMENDMENTS TO THE CREDIT AGREEMENT

                  1.1.     AMENDMENT TO SECTION 5.14 (DEBT/OPERATING CASH FLOW 
RATIO)

                  Subject to Section 2 hereof, the Bank hereby suspends the 
applicability of Sections 5.14 of the Credit Agreement (Debt/Operating Cash Flow
Ratio) for the fiscal quarter of the Borrower ending September 30, 1996.

                  1.2.     AMENDMENT TO SECTION 5.15 (INTEREST COVERAGE RATIO)

                  Subject to Section 2 hereof, the Bank hereby suspends the
applicability of Section 5.15 of the Credit Agreement (Interest Coverage Ratio)
for the fiscal quarter of the Borrower ending September 30, 1996.

         SECTION 2.   EFFECTIVENESS OF PARTICULAR SUSPENSIONS.

                  2.1.     EFFECTIVENESS OF THE SUSPENSION OF THE DEBT/OPERATING
                           CASH FLOW RATIO COVENANT.

                  The suspension of Section 5.14 of the Credit Agreement set
forth in Section 1.1 hereof shall not be effective if as of September 30, 1996
the Debt/Operating Cash Flow Ratio for the fiscal quarter of the Borrower ending
September 30, 1996 is greater than 3.0:1.

                  2.2.     EFFECTIVENESS OF THE SUSPENSION OF THE INTEREST 
                           COVERAGE RATIO COVENANT.

                  The suspension of Section 5.15 of the Credit Agreement set
forth in Section 1.2 hereof shall not be effective if as of September 30, 1996
the Operating Income of the Borrower for the fiscal quarter of the Borrower
ending September 30, 1996 is a loss greater than $4,500,000.


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                  2.3.     EFFECTIVENESS OF THE SUSPENSIONS GENERALLY.

                  Each suspension of the financial covenants set forth in
Sections 1.1 and 1.2 above is effective only with respect to the fiscal quarter
of the Borrower ending September 30, 1996. Each of Sections 5.14 and 5.15 shall
be applicable for each fiscal quarter of the Borrower ending after September 30,
1996.

         SECTION 3.   EFFECTIVENESS OF THIS AMENDMENT

                  This Amendment shall be effective upon the Bank's receipt of a
duly executed counterpart of this Amendment.

         SECTION 4.   BORROWER'S REPRESENTATIONS AND
                                   WARRANTIES

                  In order to induce the Bank to enter into this Amendment and
to amend the Credit Agreement in the manner provided herein, the Borrower
represents and warrants to the Bank that the following statements are true,
correct and complete:

                  4.1.  CORPORATE  POWER AND AUTHORITY.  The Borrower has all
requisite corporate power and authority to enter into this Amendment and to
carry out the transactions contemplated by, and perform its obligations under,
the Credit Agreement.

                  4.2.  AUTHORIZATION  OF  AGREEMENTS.  The  execution, 
delivery and performance of this Amendment and the performance of the Credit
Agreement have been duly authorized by all necessary corporate action by the
Borrower.

                  4.3. NO CONFLICT. The execution, delivery and performance by
the Borrower of this Amendment and the performance by the Borrower of the Credit
Agreement do not and will not (i) violate any provision of any law, rule or
regulation applicable to the Borrower or any of its Subsidiaries, the
Certificate of Incorporation or Bylaws of the Borrower or any of its
Subsidiaries or any order, judgment or decree of any court or other agency of
the government binding on the Borrower or any of its Subsidiaries, (ii) conflict
with, result in a breach of or constitute (with due notice or lapse of time or
both) a default under any Contract of the Borrower or any of its Subsidiaries,
(iii) result in or require the creation or imposition of any Lien upon any of
their properties or assets, or (iv) require any approval of stockholders or any
approval or consent of any Person under any Contract of the Borrower or any of
its Subsidiaries except for such approvals or consents which have been obtained
on or before the date hereof and disclosed in writing to the Bank.

                  4.4. GOVERNMENTAL CONSENTS. The execution and delivery by the
Borrower of this Amendment and the performance by the Borrower of the Credit
Agreement do not and will not require any registration with, consent or approval
of, or notice to, or other action to, with or by, any Federal, state or other
governmental authority or regulatory body or other Person.

                  4.5. BINDING OBLIGATION. This Amendment, when executed and
delivered, will be, and the Credit Agreement is, the legally valid and binding
obligations of the Borrower, enforceable against it in accordance with their
respective terms, except as enforcement may be limited by bankruptcy,
insolvency, reorganization, moratorium or other similar laws relating to or
limiting creditors' rights generally or by equitable principles relating to
enforceability.

                  4.6. INCORPORATION OR REPRESENTATIONS AND WARRANTIES FROM
CREDIT AGREEMENT. The representations and warranties contained in Article 4 of
the Credit Agreement are and will be true, correct and complete in all material
respects on and as of the date hereof to the same extent as though made on and
as of that date, except to the extent that such representations and warranties
specifically relate to an earlier date, in which case they are true, correct and
complete in all material respects as of such earlier


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 date.

                  4.7.  ABSENCE OF DEFAULT.  No event has  occurred  and is 
continuing or will result from the execution of this Amendment which would
constitute an Event of Default or a Potential Event of Default.

         SECTION 5.  MISCELLANEOUS

                  5.1.  REFERENCE TO AND EFFECT ON THE CREDIT AGREEMENT AND THE
OTHER LOAN DOCUMENTS.

                           (a) On and after the date hereof, each reference in
                  the Credit Agreement to "this Agreement", "hereunder",
                  "hereof", "herein" or words of like import referring in the
                  other Loan Documents to the "Credit Agreement", "thereunder",
                  "thereof" or words of like import referring to the Credit
                  Agreement shall mean and be a reference to the Credit
                  Agreement as amended by this Amendment.

                           (b) Except as specifically amended by this Amendment,
         the Credit Agreement, Pledge Agreement and the other Loan Documents
         shall remain in full force and effect and are hereby ratified and
         confirmed.

                           (c) The execution, delivery and performance of this
         Amendment shall not, constitute a waiver of any provision of, or
         operate as a waiver of any right, power or remedy of the Bank under,
         the Credit Agreement, the Pledge Agreement or any of the other Loan
         Documents except as may be expressly provided for herein.

                  5.2. FEES AND EXPENSES. Borrower acknowledges that all costs,
fees and expenses as described in Section 8.2 of the Credit Agreement incurred
by the Bank and its counsel with respect to this Amendment and the documents and
transactions contemplated hereby shall be for the account of the Borrower.

                  5.3. EXECUTION IN COUNTERPART. This Amendment may be executed
in any number of counterparts, and by different parties hereto in separate
counterparts, each of which when so executed and delivered shall be deemed an
original, but all such counterparts taken together shall constitute but one and
the same instrument.

                  5.4.     HEADINGS.  Section  and  subsection  headings  in 
this Amendment are included herein for convenience of reference only and shall
not constitute a apart of this Amendment for any other purpose or be given any
substantive effect.

                  5.5. APPLICABLE LAW. THIS AMENDMENT AND THE RIGHTS AND
OBLIGATIONS OF THE PARTIES HERETO AND ALL OTHER ASPECTS HEREOF SHALL BE DEEMED
TO BE MADE UNDER SHALL BE GOVERNED BY, AND SHALL BE CONSTRUED AND ENFORCED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.


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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed as of the date first above written by their respective officers
thereunto duly authorized.

                               
                                            COLLAGEN CORPORATION


                                            By:    /s/ David Foster
                                                   ----------------
                                            Name:      David Foster
                                                       ------------
                                            Title: Vice President and Chief
                                                   ------------------------
                                                   Financial Officer
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                                            THE BANK OF NEW YORK


                                            By:     /s/ Elizabeth Ying
                                                    ------------------
                                            Name:       Elizabeth Ying
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                                            Title: Vice President
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