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                                                                     Exhibit 4.2


                             STOCK OPTION AGREEMENT



STOCK OPTION AGREEMENT, dated as of April 1, 1996 (the "Effective Date") between
Viragen (Europe) Ltd., a Delaware Corporation (the "Company") and Donald Magnus
Nicolson ("Optionee").

The Company, hereby grants to Optionee a Non-Statutory Option ("NSO") to acquire
Common Stock, par value $.01 per share, of the Company (the "Common Stock"),
subject to the following terms and conditions:

         1. GRANT OF OPTION. The Company hereby grants to Optionee an NSO (the
"Option") to purchase up to 50,000 shares of Common Stock (the "Shares"), to be
transferred upon the exercise thereof, fully paid and nonassessable.

         2. EXERCISE PRICE. The exercise price of the Shares subject to the
Option shall be the lesser of (i) 70% of the opening bid price of the common
shares on the OTC Electronic Bulletin Board when such shares next commence
trading (adjusted for a planned 1:14 reversal stock split) or (ii) $7.00. The
Company shall pay all original issue or transfer taxes upon the exercise of the
Option by Optionee.

         3. EXERCISABILITY OF OPTION; RIGHTS AND PRIVILEGES. Subject to the
provisions of Paragraph 6 hereof, the Option shall be exercisable by Optionee in
whole or in part: one-half upon the Effective Date and one-half upon the first
anniversary of the Effective Date.

All granted but unexercised Options shall continue to be fully exercisable in
accordance with the provisions herein:

                           (i) if there occurs any corporate transaction that
has the result that shareholders of the Company immediately before such
transaction cease to own at least 66 2/3 percent of the voting stock of the
Company in a (a) reorganization, (b) consolidation, (c) merger, (d) liquidation
or (e) a similar of corporate transaction;

                           (ii) if the shareholders of the Company shall approve
a plan of merger, consolidation, reorganization,
liquidation or dissolution in which the Company does not survive (unless the
approved merger, consolidation, reorganization, liquidation or dissolution is
subsequently abandoned); or

                           (iii) if the shareholders of the Company shall
approve a plan for the sale, lease, exchange or other
disposition of all or substantially all the property and assets of the Company
(unless such plan is subsequently abandoned).





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         4. NON-ASSIGNABILITY OF OPTION. The Option shall not be given, granted,
sold, exchanged, transferred, pledged, encumbered, assigned or otherwise
disposed of by Optionee, other than by will or the laws of descent and
distribution, and during the lifetime of Optionee, shall not be exercisable by
any other person, but only by Optionee.

         5. METHOD OF EXERCISE OF OPTION. Optionee shall notify the Company by
written notice, in the form of the Notice of Exercise attached hereto
(Attachment A), delivered to the Company's principal office, attention: Chief
Financial Officer. At the Optionee's option, the payment for the Shares may be
made either by Optionee's check payable to the order to the Company in full
payment for the total exercise price of the number of Shares purchased or by
execution and delivery by the Optionee to the Company of a Note(s), in similar
form and content as Notes previously used by the Company for similar purposes
("Note(s)"), dated as of each Notice of Exercise. As soon as practicable after
the receipt of such Notice of Exercise and accompanying payment for the purchase
of Shares, the Company shall, at its principal office, tender to Optionee a
certificate or certificates issued in Optionee's name evidencing the Shares
purchased by Optionee hereunder.

         6. TERMINATION OF OPTION. To the extent exercisable but not exercised,
the Option shall terminate upon the first to occur of the following dates:

                  (a) five (5) years from the Exercise Date as defined herein;
or

                  (b) the expiration of ninety (90) days following the date
Optionee's employment terminates with the Company and/or any of its subsidiaries
included in the Plan with Cause, as defined in Optionee's Employment Agreement.

Subject to the provisions of this paragraph, in the event of Optionee's death,
the exercisable but unexercised portion of the Option may be exercised by the
estate of Optionee, or by the person who acquired the right to exercise the
Option by bequest or inheritance or by reason of the death of Optionee.

In the event of Optionee's termination without Cause, all granted but
unexercised Options shall continue to be fully exercisable in accordance with
the provisions herein. Additionally, in the event this Optionee's Service
Agreement dated April 1, 1996, is not renewed at the end of the Optionee's
Employment Term, then all granted but unexercised Options shall continue to be
fully exercisable in accordance with the provisions herein.

         7. PLEDGE OF SHARES. If payment for the purchase of Shares under this
Option is made through execution and delivery of a Note(s), effective upon
Optionee's purchase(s) of the Shares and the delivery of the Note(s), in order
to secure the Company's obligations under the Note(s), Optionee hereby pledges,
assigns and sets over to the Company, and grants to the Company a security
interest in, the Shares. The Shares pledged pursuant hereto shall be maintained
in escrow with Atlas, Pearlman, Trop &




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Borkson, P.A. pursuant to the terms of a Pledge and Escrow Agreement previously
used by the Company for similar purposes, which shall be executed by Optionee
and the Company upon delivery of a Note(s). As long as any Shares remain subject
to the lien of the Pledge, such Shares may not be further pledged or encumbered
in any manner, and shall not be sold, transferred or otherwise disposed of. The
Escrow Agent shall not be required to relinquish the Pledge or the Escrow
Agent's possession of the certificates evidencing the Shares, unless no later
than concurrently with the sale of the Shares pursuant to an S-8 registration,
all Notes which are secured by such Shares are paid in full. In the event any of
the Shares are to be titled in the name of an immediate family member of
Optionee or a trust pursuant to the terms herein, as a condition thereto the
designated title holder(s) of such Shares shall execute and deliver to the
Company a pledge and escrow agreement, in form and content reasonably
satisfactory to the Company and its counsel, consistent with the terms herein.
No transfer of Shares to, or designation by Optionee of (for the purposes of
owning Shares) any person or entity shall relieve Optionee of any of his
obligations under the Note(s) or this Agreement. With respect to each Note under
which a voluntary prepayment is made by Optionee, provided that interest
payments on such Note are current through the date of prepayment and such Note
is not in default and has not been accelerated, the Optionee may pay principal
to release no fewer than 5,000 shares and such shares pledged to secure such
Note shall be released from the lien of the Pledge. As long as no event of
default has occurred with respect to a Note and no event giving right to
accelerate such Note has occurred, Optionee shall retain all voting rights with
respect to all Shares securing such Note. Following an event of default or an
acceleration event, the Company shall have and may exercise all voting rights
with respect to such Shares. Optionee hereby irrevocably appoints the Company
Optionee's attorney-in-fact for such purpose, it being acknowledged that such
appointment is coupled with an interest. Any dividends or distributions payable
in respect of any Shares subject to the Pledge shall automatically be applied to
pay down the Note(s) in inverse order of their respective maturity date(s). In
the event of a default under any Note, in addition to and not in limitation or
lieu of any other rights or remedies the Company may have against Optionee as a
result of such default, the Company may exercise all of its rights at law and in
equity as a secured party, including without limitation under the Uniform
Commercial Code, with respect to all Shares then securing the Note with respect
to which the default has occurred. Upon a default, without limiting any of the
Company's other rights and remedies, the Company may conduct a public or private
foreclosure sale of the Shares securing the Note with respect to which the
default has occurred. Optionee agrees that 10 days notice to him of any private
sale is fair and reasonable. The Company may be the purchaser at any public
foreclosure sale, and may bid any commercially reasonable amount at such sale.
In all events, in the event of a public or private foreclosure sale, Optionee
shall be liable for any deficiency. All of the Company's rights and remedies
under the Note(s), the Pledge and this Agreement, and at law or in equity, are
cumulative, and none is intended to be in substitution or in lieu of, nor is the
exercise of one intended to be a waiver of, any other. The Company shall have no
obligation to proceed against the Shares before proceeding against Optionee with
respect to any default under any of the Notes.





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         8. ADJUSTMENT OF SHARES. If at any time prior to the expiration or
exercise in full of the Option, there shall be any increase or decrease in the
number of issued and outstanding shares of the Common Stock through the
declaration of a stock dividend or through any recapitalization resulting in a
stock split-up, combination or exchange of the Common Stock, then and in such
event:

                  (i) appropriate adjustment shall be made in the maximum number
of Shares available for grant, so that the same percentage of the Company's
issued and outstanding Shares shall continue to be subject to being so optioned;
and

                  (ii) appropriate adjustment shall be made in the number of
Shares, and the exercise price per Share thereof, that remain unexercised under
the Option, so that the same percentage of the Company's issued and outstanding
shares of Common Stock shall remain subject to purchase at the same aggregate
exercise price.

Except as otherwise expressly provided herein, the issuance by the Company of
shares of its capital stock of any class, or securities convertible into shares
of capital stock of any class, either in connection with a direct sale of upon
the exercise of rights or warrants to subscribe therefore, or upon conversions
of shares or obligations the Company convertible into such shares or other
securities, shall not affect, and no adjustment by reason thereof shall be made
with respect to, the number of exercise price of the Shares that remain
unexercised under the Option.

Without limiting the generality of the foregoing, the existence of unexercised
Shares under the Option shall not affect in any manner the right or power of the
Company to make, authorize or consummate (i) any or all adjustments,
recapitalizations, reorganizations or other changes in the Company's capital
structure or its business; (ii) any merger or consolidation of the Company;
(iii) any issue by the Company of debt securities, or preferred or preference
stock that would rank above the Shares issuable upon exercise of the Option;
(iv) the dissolution or liquidation of the Company; (v) any sale, transfer or
assignment of all or any part of the assets or business of the Company; or (vi)
any other corporate act or proceeding, whether of a similar character or
otherwise.

         9. NO RIGHTS AS STOCKHOLDER. Optionee shall have no rights as a
stockholder of the Company in respect of the Shares as to which the Option shall
not have been exercised and payments made therefore as herein provided.

         10. BINDING EFFECT. Except as otherwise provided herein, this Agreement
shall be binding upon and inure to the benefit of the parties hereto, their
heirs, legal representatives, successors and permitted assigns.

         11. GOVERNING LAW. This Agreement shall be governed by and construed in
accordance with the laws of the State of Delaware, without giving effect to the
conflict of laws principles thereof.





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         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
day and year first above written.


                                            VIRAGEN (EUROPE) LTD.



/s/ Patricia Zambrano                       By: /s/ Dennis W. Healey
----------------------------------              --------------------------------
Patricia Zambrano                                   Dennis W. Healey
Witness                                             Executive Vice President




                                            OPTIONEE

                                                /s/ Donald Magnus Nicolson
                                                --------------------------------
                                                    Donald Magnus Nicolson







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                                  ATTACHMENT A

                               NOTICE OF EXERCISE


The undersigned hereby irrevocably elects to exercise the within Option to the
extent of purchasing __________ shares of Common Stock of Viragen (Europe) Ltd.,
a Delaware Corporation, and hereby makes payments of $________ in payment
therefor.



                                            --------------------------
                                            Signature



                                            --------------------------
                                            Date







            INSTRUCTIONS FOR ISSUANCE OF STOCK AND CORPORATE RECORDS



Name:
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                (Please type or print in block letters)

Address:      -------------------------------------------


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Social Security #:
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Phone #: (    )
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Fax #:   (    )
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