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                                                                  EXHIBIT 10.37



                               CYTEL CORPORATION

                 1994 NON-EMPLOYEE DIRECTORS' STOCK OPTION PLAN

                           ADOPTED ON MARCH 18, 1994

                            APPROVED BY STOCKHOLDERS

                                ON JUNE 17,1994

                           AMENDED ON MARCH 15, 1996,

                              SEPTEMBER 20, 1996,

                               AND MARCH 21, 1997



1.       PURPOSE.

         (A)     The purpose of the 1994 Non-Employee Directors' Stock Option
Plan (the "Plan") is to provide a means by which each director of Cytel
Corporation (the "Company") who is not otherwise an employee of the Company or
of any Affiliate of the Company (each such person being hereafter referred to
as a "Non-Employee Director") will be given an opportunity to purchase stock of
the Company.

         (B)     The word "Affiliate" as used in the Plan means any parent
corporation or subsidiary corporation of the Company as those terms are defined
in Sections 424(e) and (f), respectively, of the Internal Revenue Code of 1986,
as amended from time to time (the "Code").

         (C)     The Company, by means of the Plan, seeks to retain the
services of persons now serving as Non-Employee Directors of the Company, to
secure and retain the services of persons capable of serving in such capacity,
and to provide incentives for such persons to exert maximum efforts for the
success of the Company.





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2.       ADMINISTRATION.

         (A)     The Plan shall be administered by the Board of Directors of
the Company (the "Board") unless and until the Board delegates administration
to a committee, as provided in subparagraph 2(b).

         (B)     The Board may delegate administration of the Plan to a
committee composed of not fewer than two (2) members of the Board (the
"Committee").  If administration is delegated to a Committee, the Committee
shall have, in connection with the administration of the Plan, the powers
theretofore possessed by the Board, subject, however, to such resolutions, not
inconsistent with the provisions of the Plan, as may be adopted from time to
time by the Board.  The Board may abolish the Committee at any time and revest
in the Board the administration of the Plan.


3.       SHARES SUBJECT TO THE PLAN.

         (A)     Subject to the provisions of paragraph 10 relating to
adjustments upon changes in stock, the stock that may be sold pursuant to
options granted under the Plan shall not exceed in the aggregate six million
four hundred thousand (6,400,000) shares of the Company's common stock less the
number of shares of the Company's common stock which has been sold under, or
may be sold pursuant to outstanding stock awards granted under, the Company's
1989 Stock Plan.  If any option granted under the Plan shall for any reason
expire or otherwise terminate without having been exercised in full, the stock
not purchased under such option shall again become available for the Plan.


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         (B)     The stock subject to the Plan may be unissued shares or
reacquired shares, bought on the market or otherwise.

4.       ELIGIBILITY.

         (A)     Options shall be granted only to Non-Employee Directors of the
Company.

5.       NON-DISCRETIONARY GRANTS.

         (A)     Each person who is, after the Adoption Date, elected for the
first time to be a Non-Employee Director shall, upon the date of his initial
election to be a Non-Employee Director by the Board or stockholders of the
Company, be granted an option to purchase twenty-five thousand (25,000) shares
of common stock of the Company on the terms and conditions set forth herein.

         (B)     On January 1 of each year, commencing with January 1, 1995,
each person who is then a Non-Employee Director and has been a Non-Employee
Director for at least three (3) months shall be granted an option to purchase
five thousand (5,000) shares of common stock of the Company on the terms and
conditions set forth herein.

6.       OPTION PROVISIONS.

         Each option shall contain the following terms and conditions:

         (A)     The term of each option commences on the date it is granted
and, unless sooner terminated as set forth herein, expires on the date
("Expiration Date") ten (10) years from the date of grant.  If the optionee's
service as a director or employee of or consultant to the Company or any
Affiliate terminates for any reason or for no reason, the option shall
terminate on the earlier of the Expiration Date or the date three (3) months







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following the date of termination of all such service; provided, however, that
if such termination of service is due to the optionee's death, the option shall
terminate on the earlier of the Expiration Date or six (6) months following the
date of the optionee's death.  In any and all circumstances, an option may be
exercised following termination of the optionee's service as a director or
employee of or consultant to the Company or any Affiliate only as to that
number of shares as to which it was exercisable on the date of termination of
all such service under the provisions of subparagraph 6(e).

         (B)     Subject to subparagraph 4(b), the exercise price of each
option shall be one hundred percent 100% of the fair market value of the stock
subject to such option on the date such option is granted.

         (C)     The exercise price of stock acquired pursuant to each option
shall be paid, to the extent permitted by applicable statutes and regulations,
either (i) in cash at the time of exercise; or (ii) by delivery of shares of
common stock of the Company already owned by the optionee, held for the period
required to avoid a charge to the Company's reported earnings, and owned free
and clear of any liens, claims, encumbrances or security interest, which common
stock shall be valued at fair market value on the date preceding the date of
exercise; or (iii) by a combination of such methods of payment.

         Notwithstanding the foregoing, this option may be exercised pursuant
to a program developed under Regulation T as promulgated by the Federal Reserve
Board which results in the receipt of cash (or check) by the Company prior to
the issuance of shares of the Company's common stock.







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         (D)     Except as otherwise expressly provided in an optionholder's
option agreement, an option shall not be transferable except by will or by the
laws of descent and distribution, and shall be exercisable during the lifetime
of the person to whom the option is granted only by such person or by his
guardian or legal representative.

         (E)     The option shall become exercisable in installments over a
period of four (4) years from the date of grant on a daily basis at the rate of
twenty-five percent (25%) per year of the total number of shares subject to the
option; provided that prior to the first anniversary of the date of
commencement of the optionee's service as a Non-Employee Director, the option
shall not be exercisable for any number of shares; and provided further that
the optionee has, during the entire period prior to such vesting date,
continuously served as a director or as an employee of or consultant to the
Company or any Affiliate of the Company, whereupon such option shall become
fully exercisable in accordance with its terms with respect to that portion of
the shares represented by that installment.

         (F)     The Company may require any optionee, or any person to whom an
option is transferred under subparagraph 6(d), as a condition of exercising any
such option:  (i) to give written assurances satisfactory to the Company as to
the optionee's knowledge and experience in financial and business matters; and
(ii) to give written assurances satisfactory to the Company stating that such
person is acquiring the stock subject to the option for such person's own
account and not with any present intention of selling or otherwise distributing
the stock.  These requirements, and any assurances given pursuant







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to such requirements, shall be inoperative if (i) the issuance of the shares
upon the exercise of the option has been registered under a then-
currently-effective registration statement under the Securities Act of 1933, as
amended (the "Securities Act"), or (ii), as to any particular requirement, a
determination is made by counsel for the Company that such requirement need not
be met in the circumstances under the then-applicable securities laws.

         (G)     Notwithstanding anything to the contrary contained herein, an
option may not be exercised unless the shares issuable upon exercise of such
option are then registered under the Securities Act or, if such shares are not
then so registered, the Company has determined that such exercise and issuance
would be exempt from the registration requirements of the Securities Act.

7.       COVENANTS OF THE COMPANY.

         (A)     During the terms of the options granted under the Plan, the
Company shall keep available at all times the number of shares of stock
required to satisfy such options.

         (B)     The Company shall seek to obtain from each regulatory
commission or agency having jurisdiction over the Plan such authority as may be
required to issue and sell shares of stock upon exercise of the options granted
under the Plan; provided, however, that this undertaking shall not require the
Company to register under the Securities Act either the Plan, any option
granted under the Plan, or any stock issued or issuable pursuant to any such
option.  If the Company is unable to obtain from any such regulatory commission
or agency the authority which counsel for the Company deems







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necessary for the lawful issuance and sale of stock under the Plan, the Company
shall be relieved from any liability for failure to issue and sell stock upon
exercise of such options.

8.       USE OF PROCEEDS FROM STOCK.

         Proceeds from the sale of stock pursuant to options granted under the
Plan shall constitute general funds of the Company.

9.       MISCELLANEOUS.

         (A)     Neither an optionee nor any person to whom an option is
transferred under subparagraph 6(d) shall be deemed to be the holder of, or to
have any of the rights of a holder with respect to, any shares subject to such
option unless and until such person has satisfied all requirements for exercise
of the option pursuant to its terms.

         (B)     Throughout the term of any option granted pursuant to the
Plan, the Company shall make available to the holder of such option, not later
than one hundred twenty (120) days after the close of each of the Company's
fiscal years during the option term, upon request, such financial and other
information regarding the Company as comprises the annual report to the
stockholders of the Company provided for in the By- laws of the Company and
such other information regarding the Company as the holder of such option may
reasonably request.

         (C)     Nothing in the Plan or in any instrument executed pursuant
thereto shall confer upon any Non-Employee Director any right to continue in
the service of the Company or any Affiliate or shall affect any right of the
Company, its Board or







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stockholders or any Affiliate to terminate the service of any Non-Employee
Director with or without cause.

         (D)     No Non-Employee Director, individually or as a member of a
group, and no beneficiary or other person claiming under or through him, shall
have any right, title or interest in or to any option reserved for the purposes
of the Plan except as to such shares of common stock, if any, as shall have
been reserved for him pursuant to an option granted to him.

         (E)     In connection with each option made pursuant to the Plan, it
shall be a condition precedent to the Company's obligation to issue or transfer
shares to a Non-Employee Director, or to evidence the removal of any
restrictions on transfer, that such Non-Employee Director make arrangements
satisfactory to the Company to insure that the amount of any federal or other
withholding tax required to be withheld with respect to such sale or transfer,
or such removal or lapse, is made available to the Company for timely payment
of such tax.

10.      ADJUSTMENTS UPON CHANGES IN STOCK.

         (A)     If any change is made in the stock subject to the Plan, or
subject to any option granted under the Plan (through merger, consolidation,
reorganization, recapitalization, stock dividend, dividend in property other
than cash, stock split, liquidating dividend, combination of shares, exchange
of shares, change in corporate structure or otherwise), the Plan and
outstanding options will be appropriately adjusted in







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the class(es) and maximum number of shares subject to the Plan and the
class(es) and number of shares and price per share of stock subject to
outstanding options.

         (B)     In the event of:  (1) a merger or consolidation in which the
Company is not the surviving corporation; (2) a reverse merger in which the
Company is the surviving corporation but the shares of the Company's common
stock outstanding immediately preceding the merger are converted by virtue of
the merger into other property, whether in the form of securities, cash or
otherwise; or (3) any other capital reorganization in which more than fifty
percent (50%) of the shares of the Company entitled to vote are exchanged, the
time during which options outstanding under the Plan may be exercised shall be
accelerated and the options terminated if not exercised prior to such event.

11.      AMENDMENT OF THE PLAN.

         (A)     The Board at any time, and from time to time, may amend the
Plan, provided, however, that the Board shall not amend the plan more than once
every six months, with respect to the provisions of the plan which relate to
the amount, price and timing of grants, other than to comport with changes in
the Code, the Employee Retirement Income Security Act, or the rules thereunder.
Except as provided in paragraph 10 relating to adjustments upon changes in
stock, no amendment shall be effective unless approved by the stockholders of
the Company within twelve (12) months before or after the adoption of the
amendment, where the amendment will:

                 (I)      Increase the number of shares which may be issued
under the Plan;







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                 (II)     Modify the requirements as to eligibility for
participation in the Plan (to the extent such modification requires stockholder
approval in order for the Plan to comply with the requirements of Rule 16b-3);
or

                 (III)    Modify the Plan in any other way if such modification
requires stockholder approval in order for the Plan to comply with the
requirements of Rule 16b-3.

         (B)     Rights and obligations under any option granted before any
amendment of the Plan shall not be altered or impaired by such amendment unless
(i) the Company requests the consent of the person to whom the option was
granted and (ii) such person consents in writing.

12.      TERMINATION OR SUSPENSION OF THE PLAN.

         (A)     The Board may suspend or terminate the Plan at any time.
Unless sooner terminated, the Plan shall terminate on March 17, 2004.  No
options may be granted under the Plan while the Plan is suspended or after it
is terminated.

         (B)     Rights and obligations under any option granted while the Plan
is in effect shall not be altered or impaired by suspension or termination of
the Plan, except with the consent of the person to whom the option was granted.

         (C)     The Plan shall terminate upon the occurrence of any of the
events described in Section 10(b) above.








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13.      EFFECTIVE DATE OF PLAN; CONDITIONS OF EXERCISE.

         (A)     The Plan shall become effective upon adoption by the Board of
Directors, subject to the condition subsequent that the Plan is approved by the
stockholders of the Company.

         (B)     No option granted under the Plan shall be exercised or
exercisable unless and until the condition of subparagraph 13(a) above has been
met.









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