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                                                                    Exhibit 4.36

                         Control Delivery Systems, Inc.

                                  Stock Option
                    Granted Under the 1997 Stock Option Plan
                    ----------------------------------------

     Stock Option granted by Control Delivery Systems, Inc., a Delaware
corporation (the "Company"), to Paul Ashton (the "Optionee") pursuant to the
Company's 1997 Stock Option Plan (the "Plan").

1.   Grant of Option.
     ---------------

     This certificate evidences the grant by the Company on September 18, 1997
to Optionee of an option to purchase, in whole or in part, on the terms herein
provided, a total of 15,000 shares of common stock of the Company (the
"Shares") at $6.25 per Share, which is not less than the fair market value of
the Shares on the date of grant of this option. This option must be exercised
before 5:00 p.m., E.S.T. on September 18, 2007 ("Final Exercise Date").

     This option is exercisable in the following installments prior to the
Final Exercise Date:

up to 3,750 shares on and after September 18, 1998;
up to an additional 3,750 shares on and after September 18, 1999;
up to an additional 3,750 shares on and after September 18, 2000; and
up to an additional 3,750 shares on and after September 18, 2001.

2.   Exercise of Option.

     Each election to exercise this option shall be in writing, signed by the
Optionee or Optionee's executor or administrator or the person or persons to
whom this option is transferred by will or the applicable laws of descent and
distribution (the "Legal Representative"), and received by the Company at its
principal office, accompanied by this certificate, and payment in full as
provided in the Plan. The exercise price may be paid by delivery of cash, a
certified check, bank draft or money order payable to the Company, common stock
of the Company which have been outstanding at least six months and which have a
fair market value equal to an unconditional and irrevocable undertaking by a
broker to deliver promptly to the Company sufficient funds to pay the exercise
price, or any combination of the foregoing. In the event that this option is
exercised by the Optionee's Legal Representative, the Company shall be under no
obligation to deliver Shares hereunder unless and until the Company is
satisfied as to the authority of the person or persons exercising this option.

3.   Notice of Disposition.
     ---------------------

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     The person exercising this option shall notify the Company when making any
disposition of the Shares acquired upon exercise of this option, whether by
sale, gift or otherwise.

4.   Application of Stock Transfer Agreement.

     If at the time this option is exercised the Company is a party to any
agreement restricting the transfer of any outstanding shares of its Common
Stock, this option may be exercised only if the Shares so acquired are made
subject to the transfer restrictions set forth in that agreement (or if more
than one such agreement is then in effect, the agreement specified by the Board
of Directors of the Company).

5.   Withholding.

     No Shares will be issued pursuant to the exercise of this option unless and
until the person exercising this option shall have remitted to the Company an
amount sufficient to satisfy any federal, state or local withholding tax
requirements, or shall have made other arrangements satisfactory to the Company
with respect to such taxes.

6.   Nontransferability of Option.

     This option is not transferable by the Optionee otherwise than by will or
the laws of descent and distribution, and is exercisable during the Optionee's
lifetime only by the Optionee.

7.   Provisions of the Plan.

     This option is subject to the provisions of the Plan, as amended from time
to time, which shall be controlling in the event of any conflicting or
inconsistent provisions. A copy of the Plan has been provided to the Optionee
previously.

     IN WITNESS WHEREOF, the Company has caused this option to be executed under
its corporate seal by its duly authorized officer. This option shall take effect
as a sealed instrument.


                                       Control Delivery Systems, Inc.

                                       By: /s/ Michael J. Soja
                                           --------------------------

Dated: July 10, 2002


                                      -2-
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                         Control Delivery Systems, Inc.

                             Incentive Stock Option
                    Granted Under the 1997 Stock Option Plan

     Incentive Stock Option granted by Control Delivery Systems, Inc., a
Delaware corporation (the "Company"), to Paul Ashton (the "Optionee") pursuant
to the Company's 1997 Stock Option Plan (the "Plan").

1.   Grant of Option

     This certificate evidences the grant by the Company on August 26, 1999 to
Optionee of an option to purchase, in whole or in part, on the terms herein
provided, a total of 10,000 shares of common stock of the Company (the "Shares")
at $8.00 per Share, which is not less than [110%] of the fair market value of
the Shares on the date of grant of this option. This option must be exercised
before 5:00 p.m., E.S.T. on August 25, 2009 ("Final Exercise Date"). It is
intended that the option evidenced by this certificate shall be an incentive
stock option as defined in section 422 of the Internal Revenue Code of 1986, as
amended from time to time, (the "Code").

     This option is exercisable in the following installments prior to the
Final Exercise Date:

up to 3,333 shares on and after August 26, 2000;
up to an additional 3,333 shares on and after August 26, 2001; and
up to an additional 3,334 shares on and after August 26, 2002.

2.   Exercise of Option.

     Each election to exercise this option shall be in writing, signed by the
Optionee or Optionee's executor or administrator or the person or persons to
whom this option is transferred by will or the applicable laws of descent and
distribution (the "Legal Representative"), and received by the Company at its
principal office, accompanied by this certificate, and payment in full as
provided in the Plan. The exercise price may be paid by delivery of cash, a
certified check, bank draft or money order payable to the Company, common stock
of the Company which have been outstanding at least six months and which have a
fair market value equal to an unconditional and irrevocable undertaking by a
broker to deliver promptly to the Company sufficient funds to pay the exercise
price, or any combination of the foregoing. In the event that this option is
exercised by the Optionee's Legal Representative, the Company shall be under no
obligation to deliver Shares hereunder unless and until the Company is
satisfied as to the authority of the person or persons exercising this option.

                                      -1-
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3.   Notice of Disposition.

     The person exercising this option shall notify the Company when making any
disposition of the Shares acquired upon exercise of this option, whether by
sale, gift or otherwise.

4.   Application of Stock Transfer Agreement.

     If at the time this option is exercised the Company is a party to any
agreement restricting the transfer of any outstanding shares of its Common
Stock, this option may be exercised only if the Shares so acquired are made
subject to the transfer restrictions set forth in that agreement (or if more
than one such agreement is then in effect, the agreement specified by the Board
of Directors of the Company).

5.   Withholding

     No Shares will be issued pursuant to the exercise of this option unless
and until the person exercising this option shall have remitted to the Company
an amount sufficient to satisfy any federal, state or local withholding tax
requirements, or shall have made other arrangements satisfactory to the Company
with respect to such taxes.

6.   Nontransferability of Option.

     This option is not transferable by the Optionee otherwise than by will or
the laws of descent and distribution, and is exercisable during the Optionee's
lifetime only by the Optionee.

7.   Provisions of the Plan.

     This option is subject to the provisions of the Plan, as amended from time
to time, which shall be controlling in the event of any conflicting or
inconsistent provisions. A copy of the Plan has been provided to the Optionee
previously.



     IN WITNESS WHEREOF, the Company has caused this option to be executed
under its corporate seal by its duly authorized officer. This option shall take
effect as a sealed instrument.


                                       Control Delivery Systems, Inc.


                                       By /s/ ILLEGIBLE
                                          -----------------------------


Dated: July 10, 2002
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ASHTON P. 8.26.99                      -2-