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                                                                   EXHIBIT 4.1

THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE 
SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"), OR UNDER THE SECURITIES LAWS 
OF CERTAIN STATES.  THESE SECURITIES ARE SUBJECT TO RESTRICTIONS ON 
TRANSFERABILITY AND RESALE AND MAY NOT BE TRANSFERRED OR RESOLD EXCEPT AS 
PERMITTED UNDER THE ACT AND THE APPLICABLE STATE SECURITIES LAWS, PURSUANT TO 
REGISTRATION OR EXEMPTION THEREFROM.  INVESTORS SHOULD BE AWARE THAT THEY MAY 
BE REQUIRED TO BEAR THE FINANCIAL RISKS OF THIS INVESTMENT FOR AN INDEFINITE 
PERIOD OF TIME.  THE ISSUER OF THESE SECURITIES MAY REQUIRE AN OPINION OF 
COUNSEL IN FORM AND SUBSTANCE SATISFACTORY TO THE ISSUER TO THE EFFECT THAT 
ANY PROPOSED TRANSFER OR RESALE IS IN COMPLIANCE WITH THE ACT AND ANY 
APPLICABLE STATE SECURITIES LAWS.


                                AQUASEARCH, INC.

                                PROMISSORY NOTE


$___________                                                Kailua-Kona, Hawaii
                                                                 August 1, 1996

     FOR VALUE RECEIVED, AQUASEARCH, INC., a Colorado corporation (the 
"Company") hereby absolutely and unconditionally promises to pay to
____________________________ (the "Lender"), or order, the principal amount of
__________________________________ ($_________), together with simple interest
at the rate of six and one-quarter percent (6.25%) per annum (calculated on the
basis of twelve 30-day months).  Accrued interest shall be due and payable in
cash only at the time the principal amount of this Note becomes due and owing.

     This Note is one of a series of Notes issued pursuant to the Note and
Warrant Purchase Agreement dated as of August 1, 1996 (as amended and in effect
from time to time, the "Purchase Agreement") by and among the Company, the
Lender, and certain other lenders named in Exhibit A thereto (the Lender and 
the certain other lenders are referred to herein as the "Lenders").  All 
rights under this Note rank equally with all rights under all other Notes, 
and no holder of this Note shall have rights senior to the rights of the 
holders of all or any other Notes.

     1.   REPAYMENTS AND PREPAYMENTS.

          (a)  This Note shall be due and payable on September 30, 1996; 
PROVIDED, HOWEVER, that if the $200,000 due to the Company upon receipt of 
shareholder approval of that certain Distribution and Development Agreement 
and Stock Subscription Agreement, each dated as of May 14, 1996, between the 
Company and Cultor, Ltd. (the "Cultor Payment") is paid to the Company before 
September 30, 1996, then one half of the principal amount of this Note 
(including interest) shall become due and 

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payable to the holder of this Note within five business days after receipt by 
the Company of the $200,000 Cultor Payment; and, PROVIDED, FURTHER, that any 
outstanding principal amount of this Note shall become immediately due and 
payable (including interest) upon the closing (the "First Closing") of any 
sale of equity securities of the Company before September 30, 1996.  Any 
payment of this Note shall be made only at the same time as the Company pays 
all other Notes issued pursuant to the Purchase Agreement, with such payments 
to be made pro-rata in proportion to the then outstanding principal amounts 
of such Notes.  In the event that the Company fails to pay any portion of the 
principal or interest on this Note when due upon the receipt of the Cultor 
Payment or upon the First Closing, then the Lender shall thereafter have the 
option to receive all or any portion of the interest due on this Note in the 
form of Common Stock valued at the lower of $0.56 per share or the lowest 
price at which units are sold in the Company's proposed private placement of 
units consisting of one share of Common Stock and one Warrant to Purchase One 
Share of Common Stock.  Interest shall continue to accrue on this Note until 
such time as all principal and interest due is paid in full.

          (b)  The Company may prepay this Note at any time, either in whole 
or in part, without premium or penalty and without the prior consent of the 
Lender. Any prepayment of this Note shall be made only at the same time as 
the Company prepays all other Notes issued pursuant to the Purchase 
Agreement, with such prepayments to be made pro-rata in proportion to the 
then outstanding principal amounts of such Notes.

     2.   EVENTS OF DEFAULT; ACCELERATION.  

          (a)  The principal amount of this Note is subject to prepayment in 
whole or in part upon the occurrence and during the continuance of any of the 
following events (each, an "Event of Default"):  (i) failure to pay any 
amount owing by the Company hereunder when due and payable, or (ii) the 
initiation of any bankruptcy, insolvency, moratorium, receivership or 
reorganization by or against the Company, or a general assignment of assets 
by the Company for the benefit of creditors.  Upon the occurrence of any 
Event of Default, the entire unpaid principal balance of this Note shall be 
immediately due and payable.

          (b)  No remedy herein conferred upon the Lender is intended to be 
exclusive of any other remedy and each and every remedy shall be cumulative 
and in addition to every other remedy hereunder, and under the Purchase 
Agreement, now or hereafter existing at law or in equity or otherwise.

     3.   NOTICES.  

          (a)  All notices, reports and other communications required or 
permitted hereunder shall be in writing and may be delivered in person, by 
telecopy with written confirmation, via overnight delivery service or U.S. 
mail, in which event it may be mailed by first-class, certified or 
registered, postage fully prepaid, addressed (i) if to a Lender, at such 
Lender's address set forth in the Schedule of Investors attached as Exhibit A 
to the Purchase Agreement (or such other address as such Lender shall have 
furnished the Company in writing) and (ii) if to the Company, at the address 
set forth at the 


                                      -2-
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beginning of the Purchase Agreement (or such other address as the Company 
shall have furnished the Lenders in writing), attention of Mark E. Huntley, 
Ph.D., President and Chief Executive Officer.

          (b)  Each such notice, report or other communication shall for all 
purposes under this Note be treated as effective or having been given when 
delivered if delivered personally or, if sent by mail, at the earlier of its 
receipt or 72 hours after the same has been deposited in a regularly 
maintained receptacle for the deposit of the United States mail, addressed 
and mailed as aforesaid, or, if sent by telecopier with written confirmation, 
at the earlier of (i) 24 hours after confirmation of transmission by the 
sending telecopier machine or (ii) delivery of written confirmation.

     4.   MISCELLANEOUS.

          (a)  With the written consent of the record holders of more than 
66 2/3% of the principal amount of the Notes then outstanding, the obligations 
of the Company and the rights of the holders under the Notes may be waived 
(either generally or in a particular instance, either retroactively or 
prospectively and either for a specified period of time or indefinitely), and 
with the same consent the Company, when authorized by resolution of its Board 
of Directors, may enter into a supplementary agreement for the purpose of 
adding any provisions to or changing in any manner or eliminating any of the 
provisions of this Note; PROVIDED, HOWEVER, that no such waiver or 
supplemental agreement shall reduce the above percentage of principal amount, 
the holders of which are required to consent to any waiver or supplemental 
agreement, without the consent of the record or beneficial holders of all of 
the Notes, nor increase the obligations of any holder of a Note without such 
holder's written consent.  Upon the effectuation of each such waiver, 
consent, agreement, amendment or modification, the Company shall promptly 
give written notice thereof to the record holders of the Notes who have not 
previously consented thereto in writing.  Neither this Note nor any 
provisions hereof may be changed, waived, discharged or terminated orally, 
but only by a signed statement in writing.

          (b)  No failure or delay by the Lender to exercise any right 
hereunder shall operate as a waiver thereof, nor shall any single or partial 
exercise of any right, power or privilege preclude any other right, power or 
privilege.  The provisions of this Note are severable and if any one 
provision hereof shall be held invalid or unenforceable in whole or in part 
in any jurisdiction, such invalidity or unenforceability shall affect only 
such provision in such jurisdiction.  This Note expresses the entire 
understanding of the parties with respect to the transactions contemplated 
hereby.  The Company and every endorser and guarantor of this Note regardless 
of the time, order or place of signing hereby waives presentment, demand, 
protest and notice of every kind, and assents to any extension or 
postponement of the time for payment or any other indulgence, to any 
substitution, exchange or release of collateral, and to the addition or 
release of any other party or person primarily or secondarily liable.

          (c)  If Lender retains an attorney for collection of this Note, or 
if any suit or proceeding is brought for the recovery of all, or any part of, 
or for protection of the indebtedness respected by this Note, then the 
Company agrees to pay on demand all costs and expenses of the suit or 
proceeding, or any appeal thereof, incurred by the Lender, including without 
limitation, reasonable attorneys' fees.


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          (d)  This Note shall for all purposes be governed by, and construed 
in accordance with the laws of the State of California (without reference to 
conflict of laws).

          (e)  This Note shall be binding upon the Company's successors and 
assigns, and shall inure to the benefit of the Lender's successors and 
assigns.

     IN WITNESS WHEREOF, the Company has caused this Note to be executed by 
its duly authorized officer to take effect as of the date first hereinabove 
written.


                              AQUASEARCH, INC.


                              By:
                                   -------------------------------------
                                   Mark E. Huntley, Ph.D.
                                   President and Chief Executive Officer