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                                SUBSCRIPTION AGREEMENT
                           -------------------------------

                            ENERGY BIOSYSTEMS CORPORATION

                           -------------------------------

                           7,500,000 SHARES OF COMMON STOCK

                           -------------------------------

To:  Energy BioSystems Corporation

This Subscription Agreement (this "Subscription Agreement" or the "Agreement")
is made between Energy BioSystems Corporation, a Delaware corporation in the
development stage, (the "Company"), and the undersigned prospective purchaser
who is subscribing hereby for shares (the "Shares") of the Company's Common
Stock, $.001 par value ("Common Stock").  This subscription is submitted to you
in accordance with and subject to the terms and conditions described in this
Subscription Agreement and the Confidential Private Placement Memorandum dated
April 16, 1999, as amended by Supplement dated May 26, 1999 to Confidential
Private Placement Memorandum (as it may be supplemented or updated from time to
time, the "Memorandum"), relating to the offering (the "Offering") of 7,500,000
Shares.  The closing of the Offering is subject to stockholder approval.  The
purchase price per Share is as set forth in the Memorandum.

In consideration of the Company's agreement to sell Shares to the undersigned
upon the terms and conditions summarized in the Memorandum, the undersigned
agrees and represents as follows:

A.   SUBSCRIPTION

     (1)  The undersigned hereby irrevocably subscribes for and agrees to
          purchase the number of Shares indicated on the signature page hereto
          at a purchase price per Share as set forth in the Memorandum. The
          minimum subscription is $100,000, provided that the Company may, in
          its sole discretion, accept subscriptions for less than such amount.
          The undersigned encloses herewith a check payable to "Energy
          BioSystems Corporation--Escrow Account" for the full amount of the
          purchase price of the Shares for which the undersigned is subscribing
          (the "Payment").  The undersigned hereby acknowledges that the actual
          number of Shares which the undersigned will receive will be equal to
          the amount of the undersigned's subscription divided by the Purchase
          Price for the Shares as defined in the Memorandum.

     (2)  The undersigned understands that all payments by check of the
          subscription amount provided in Paragraph (1) above shall be delivered
          to SAMCO Capital Markets, Inc. (the "Placement Agent") and,
          thereafter, such payment will be deposited as soon as practicable for
          the undersigned's benefit in a non-interest bearing escrow account.
          The payment (or, in the case of rejection of a portion of the
          undersigned's subscription, the part of the payment relating to such
          rejected portion) will be returned promptly, without interest, if the
          undersigned's subscription is rejected in whole or in part.  The
          Placement Agent and the

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          Company expect to hold a closing of the Offering (the "Closing") at
          any time after subscriptions for 1,000,000 Shares have been accepted
          and the stockholders of the Company have approved the Offering at a
          duly called meeting. Upon receipt by the Company of the requisite
          payment for all Shares to be purchased by the subscribers whose
          subscriptions are accepted (each, a "Purchaser" and, collectively,
          the "Purchasers") at the Closing, the Shares so purchased will be
          issued in the name of each Purchaser, and the name of such Purchaser
          will be registered on the books of the Company as the record owner
          of such Shares.  The Company will issue to each Purchaser the stock
          certificates representing the Shares purchased. The Shares may not
          be transferred prior to the Closing.

     (3)  The undersigned hereby acknowledges receipt of a copy of the
          Memorandum, and hereby agrees to be bound thereby upon the (i)
          execution and delivery to the Company, in care of the Placement Agent,
          of the signature page to this Subscription Agreement, and (ii)
          acceptance at the Closing by the Company of the undersigned's
          subscription (the "Subscription").

     (4)  The undersigned agrees that the Company may, in its sole and absolute
          discretion, reduce the undersigned's subscription to any amount of
          Shares that in the aggregate does not exceed the amount of Shares
          hereby applied for without any prior notice to or further consent by
          the undersigned.  The undersigned hereby irrevocably constitutes and
          appoints the Placement Agent and each officer of the Placement Agent,
          each of the foregoing acting singly, in each case with full power of
          substitution, the true and lawful agent and attorney-in-fact of the
          undersigned, with full power and authority in the undersigned's name,
          place and stead, to amend this Subscription Agreement and the
          Questionnaire, including in each case the undersigned's signature page
          thereto, to effect any of the foregoing provisions of this Paragraph
          (4).

     (5)  The undersigned acknowledges that (i) the issuance of the Shares is
          subject to the approval of the stockholders of the Company at a duly
          called meeting; (ii) the Company cannot assure the undersigned that it
          will be able to obtain favorable votes from the required number of
          stockholders at the meeting; and (iii) in the event that the Company
          does not obtain the required stockholder approval, the Company will
          refund the undersigned's subscription without interest.  The Company
          agrees that it will submit the Offering to its stockholders for
          approval at the 1999 Meeting of Stockholders of the Company which is
          anticipated to be held on or before May 31, 1999.  Upon approval of
          the Offering by stockholders owning a majority of the outstanding
          shares entitled to vote at the meeting, and assuming that subscription
          for the minimum amount required have been received, the Company may
          conduct a closing on the Offering.

B.   REPRESENTATIONS, WARRANTIES AND VOTING AGREEMENT

The undersigned hereby represents and warrants to, and agrees with, the Company
and the Placement Agent as follows:

     (1)  The undersigned has been furnished with and has carefully read the
          Memorandum (including the Attachments thereto) and this Agreement and
          is familiar with and understands the terms of the Offering.  The
          undersigned has carefully considered and has, to the extent the
          undersigned believes such discussion necessary, discussed with the
          undersigned's

                                      -2-

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          professional legal, tax, accounting and financial advisors the
          suitability of an investment in the Shares for the undersigned's
          particular tax and financial situation and has determined that the
          Shares being subscribed for by the undersigned are a suitable
          investment for the undersigned.

     (2)  The undersigned acknowledges that (i) the undersigned has had the
          right to request copies of any documents, records, and books
          pertaining to this investment and (ii) any such documents, records and
          books which the undersigned requested have been made available for
          inspection by the undersigned, the undersigned's attorney, accountant
          or adviser(s).

     (3)  The undersigned and/or the undersigned's adviser(s) has/have had a
          reasonable opportunity to ask questions of and receive answers from a
          person or persons acting on behalf of the Company concerning the
          Offering and all such questions have been answered to the full
          satisfaction of the undersigned.

     (4)  The undersigned is not subscribing for Shares as a result of or
          subsequent to any advertisement, article, notice or other
          communication published in any newspaper, magazine or similar media or
          broadcast over television or radio or presented at any seminar or
          meeting.

     (5)  If the undersigned is a natural person, the undersigned has reached
          the age of majority in the state in which the undersigned resides, has
          adequate means of providing for the undersigned's current financial
          needs and contingencies, is able to bear the substantial economic
          risks of an investment in the Shares for an indefinite period of time,
          has no need for liquidity in such investment and, at the present time,
          could afford a complete loss of such investment.

     (6)  The undersigned or the undersigned's purchaser representative, as the
          case may be, has had such knowledge and experience in financial, tax
          and business matters so as to enable the undersigned to utilize the
          information made available to the undersigned in connection with the
          Offering to evaluate the merits and risks of an investment in the
          Shares and to make an informed investment decision with respect
          thereto.

     (7)  The undersigned will not sell or otherwise transfer the Shares without
          registration under the Securities Act of 1933, as amended (the
          "Securities Act"), or applicable state securities laws or an exemption
          therefrom.  None of the Shares have been registered under the
          Securities Act or under the securities laws of any state.  The
          undersigned represents that the undersigned is purchasing the Shares
          for the undersigned's own account, for investment and not with a view
          toward resale or distribution.  The undersigned has not offered or
          sold the Shares being acquired nor does the undersigned have any
          present intention of selling, distributing or otherwise disposing of
          such Shares either currently or after the passage of a fixed or
          determinable period of time or upon the occurrence or non-occurrence
          of any predetermined event or circumstances in violation of the
          Securities Act.  The undersigned is aware that there is currently no
          market for the Shares.  The undersigned is aware that an exemption
          from the registration requirements of the Securities Act pursuant to
          Rule 144 promulgated thereunder is not presently available; and the
          Company has no obligation to register the Shares subscribed for
          hereunder, except as provided in Paragraph D hereof, or to make
          available an exemption from the registration requirements pursuant to
          such Rule 144 or any successor rule for resale of the Shares.

                                     -3-

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     (8)  The undersigned recognizes that investment in the Shares involves
          substantial risks, including loss of the entire amount of such
          investment.  Further, the undersigned has carefully read and
          considered the matters set forth under the caption "Risk Factors" in
          the Memorandum, and has taken full cognizance of and understands all
          of the risks related to the purchase of the Shares.

     (9)  The undersigned acknowledges that the certificate representing the
          Shares shall be stamped or otherwise imprinted with a legend
          substantially in the following form:

          "The Shares represented hereby have not been registered under the
          Securities Act of 1933, as amended, or any state securities laws and
          neither the Shares nor any interest therein may be offered, sold,
          transferred, pledged or otherwise disposed of except pursuant to an
          effective registration under such act and such laws, which, in the
          opinion of counsel for the holder, which counsel and opinion are
          reasonably satisfactory to counsel for this corporation, is
          available."

     (10) If this Subscription Agreement is executed and delivered on behalf of
          a partnership, corporation, trust or estate:  (i) such partnership,
          corporation, trust or estate has the full legal right and power and
          all authority and approval required (a) to execute and deliver, or
          authorize execution and delivery of, this Subscription Agreement and
          all other instruments executed and delivered by or on behalf of such
          partnership, corporation, trust or estate in connection with the
          purchase of its Shares, (b) to delegate authority pursuant to power of
          attorney and (c) to purchase and hold such Shares; (ii) the signature
          of the party signing on behalf of such partnership, corporation, trust
          or estate is binding upon such partnership, corporation, trust or
          estate; and (iii) such partnership, corporation or trust has not been
          formed for the specific purpose of acquiring such Shares, unless each
          beneficial owner of such entity is qualified as an accredited investor
          within the meaning of Rule 501(a) of Regulation D promulgated under
          the Securities Act and has submitted information substantiating such
          individual qualification.

     (11) If the undersigned is a retirement plan or is investing on behalf of a
          retirement plan, the undersigned acknowledges that investment in the
          Shares poses additional risks including the inability to use losses
          generated by an investment in the Shares to offset taxable income.

     (12) The information contained in the Questionnaire delivered by the
          undersigned in connection with this Agreement (the "Questionnaire") is
          complete and accurate in all respects.  The undersigned shall
          indemnify and hold harmless the Company, the Placement Agent and each
          officer, director or control person of any such entity, who is or may
          be a party or is or may be threatened to be made a party to any
          threatened, pending or completed action, suit or proceeding, whether
          civil, criminal, administrative or investigative, by reason of or
          arising from any actual or alleged misrepresentation or misstatement
          of facts or omission to represent or state facts made or alleged to
          have been made by the undersigned to the Company, the Placement Agent
          (or any agent or representative of any of them) or omitted or alleged
          to have been omitted by the undersigned, concerning the undersigned or
          the undersigned's authority to invest or financial position in
          connection with the Offering, including, without limitation, any such
          misrepresentation, misstatement of omission contained in the
          Subscription Agreement or any other document submitted by the
          undersigned, against losses, liabilities and expenses for which the
          Company, the Placement Agent, or any officer, director or control
          person of any such entity has not otherwise been

                                      -4-

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          reimbursed (including attorney's fees, judgments, fines and amounts
          paid in settlement) actually and reasonably incurred by the Company,
          the Placement Agent, or such officer, director or control person in
          connection with such action, suit or proceeding.

     (13) The undersigned agrees that it will vote all of its shares of voting
          capital stock of the Company owned by it in favor of the Offering and
          the issuance of Company Common Stock in connection with the Offering
          at the 1999 Meeting of Stockholders of the Company anticipated to be
          held on or before May 31, 1999, as described.

C.   UNDERSTANDINGS.

     The undersigned understands, acknowledges and agrees with the Company and
     the Placement Agent as follows:

     (1)  This Subscription may be rejected, in whole or in part, by the Company
          or the Placement Agent, in the sole and absolute discretion of either
          of them, at any time before the Closing, notwithstanding prior receipt
          by the undersigned of notice of acceptance of the undersigned's
          Subscription.  The Company may terminate this Offering at any time in
          its sole discretion.  The execution of this Agreement or solicitation
          of the investment contemplated hereby shall create no obligation of
          the Company to accept any subscription or complete the Offering.

     (2)  Except as set forth in Section C(1)  above, the undersigned hereby
          acknowledges and agrees that the subscription hereunder is irrevocable
          by the undersigned, that, except as required by law, the undersigned
          is not entitled to cancel, terminate or revoke this Agreement or any
          agreements of the undersigned hereunder and that this Agreement and
          such other agreements shall survive the death or disability of the
          undersigned and shall be binding upon and inure to the benefit of the
          parties and their heirs, executors, administrators, successors, legal
          representatives and permitted assigns; provided, however, that the
          Company has received commitment and funds for the minimum amount
          required for closing as described in the Memorandum.  If the
          undersigned is more than one person, the obligations of the
          undersigned hereunder shall be joint and several and the agreements,
          representations, warranties and acknowledges herein contained shall be
          deemed to be made by and be binding upon each such person and his/her
          heirs, executors, administrators, successors, legal representatives
          and permitted assigns.

     (3)  No federal or state agency has made any finding or determination as to
          the accuracy or adequacy of the Memorandum or as to the fairness of
          the terms of this offering for investment nor any recommendation or
          endorsement of the Shares.

     (4)  The Offering is intended to be exempt from registration under the
          Securities Act by virtue of Section 4(2) of the Securities Act and the
          provisions of Regulation D thereunder, which is in part dependent upon
          the truth, completeness and accuracy of the statements made by the
          undersigned herein and in the Questionnaire.

     (5)  There is no public or other market for the Shares and no such public
          or other market may ever develop.  There can be no assurance that the
          undersigned will be able to sell or dispose of the Shares.  It is
          understood that in order not to jeopardize the Offering's exempt
          status

                                       -5-

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          under Section 4(2) of the Securities Act and Regulation D, any
          transferee may, at a minimum, be required to fulfill the investor
          suitability requirements thereunder.

     (6)  The undersigned acknowledges that the information contained in the
          Memorandum is confidential and non-public and agrees that all such
          information shall be kept in confidence by the undersigned and neither
          used for the undersigned's personal benefit (other than in connection
          with this subscription) nor disclosed to any third party for any
          reason; provided, however, that this confidentiality obligation shall
          not apply to any such information that (i) is part of the public
          knowledge or literature and readily accessible at the date hereof,
          (ii) becomes part of the public knowledge or literature and readily
          accessible by publication (except as a result of a breach of this
          provision) or (iii) is received from third parties (except third
          parties who disclose such information in violation of any
          confidentiality agreements or obligations, including, without
          limitation, any Subscription Agreement entered into with the Company).

     (7)  The undersigned acknowledges that the foregoing restrictions on the
          undersigned's use and disclosure of any such confidential, non-public
          information contained in the Memorandum restricts the undersigned from
          trading in the Company's securities to the extent such trading is
          based on such confidential, non-public information.

     (8)  The representations, warranties and agreements of the undersigned
          contained herein and in any other writing delivered in connection with
          the transactions contemplated hereby shall be true and correct in all
          respects on and as of the sale of the Shares as if made on and as of
          such date and shall survive the execution and delivery of this
          agreement and the purchase of the Shares.

     (9)  Insofar as indemnification for liabilities under the Securities Act
          may be permitted to directors, officers or controlling persons of the
          Company, the Company has been informed that in the opinion of the
          Securities and Exchange Commission such indemnification is against
          public policy as expressed in such Act and is therefore unenforceable
          to such extent.

     (10) IN MAKING AN INVESTMENT DECISION PURCHASERS MUST RELY ON THEIR OWN
          EXAMINATION OF THE COMPANY AND THE TERMS OF THE OFFERING, INCLUDING
          THE MERITS AND RISKS INVOLVED.  THE SHARES OFFERED HEREBY HAVE NOT
          BEEN RECOMMENDED BY ANY FEDERAL OR STATE SECURITIES COMMISSION OR
          REGULATORY AUTHORITY.  FURTHERMORE, THE FOREGOING AUTHORITIES HAVE NOT
          CONFIRMED THE ACCURACY OR DETERMINED THE ADEQUACY OF THE MEMORANDUM OR
          THIS DOCUMENT.  ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL
          OFFENSE.

     (11) THE SHARES OFFERED HEREBY MAY NOT BE TRANSFERRED, RESOLD OR OTHERWISE
          DISPOSED OF EXCEPT AS PERMITTED UNDER THE SECURITIES ACT AND
          APPLICABLE STATE SECURITIES LAWS, PURSUANT TO REGISTRATION OR
          EXEMPTION THEREFROM.  PURCHASERS SHOULD BE AWARE THAT THEY WILL BE
          REQUIRED TO BEAR THE FINANCIAL RISKS OF THIS INVESTMENT FOR AN
          INDEFINITE PERIOD OF TIME.

                                       -6-

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     (12) For Residents of Arkansas:

          THE SHARES OFFERED HEREBY ARE OFFERED PURSUANT TO A CLAIM OF EXEMPTION
          UNDER SECTION 23-42-504(a)(14) OF THE ARKANSAS SECURITIES ACT AND
          SECTION 4(2) OF THE SECURITIES ACT OF 1933.  A REGISTRATION STATEMENT
          RELATING TO THESE SHARES HAS NOT BEEN FILED WITH THE ARKANSAS
          SECURITIES DEPARTMENT OR WITH THE SECURITIES AND EXCHANGE COMMISSION.
          NEITHER THE DEPARTMENT NOR THE COMMISSION HAS PASSED UPON THE VALUE OF
          THE SHARES OFFERED HEREBY, MADE ANY RECOMMENDATIONS AS TO THEIR
          PURCHASE, APPROVED OR DISAPPROVED THE OFFERING, OR PASSED UPON THE
          ADEQUACY OR ACCURACY OF THIS MEMORANDUM.  ANY REPRESENTATION TO THE
          CONTRARY IS UNLAWFUL.

     (13) For Residents of California:

          THE SALE OF THE SHARES WHICH ARE THE SUBJECT OF THIS SUBSCRIPTION
          AGREEMENT HAS NOT BEEN QUALIFIED WITH THE COMMISSIONER OF CORPORATIONS
          OF THE STATE OF CALIFORNIA AND THE ISSUANCE OF SUCH SHARES OR THE
          PAYMENT OR RECEIPT OF ANY PART OF THE CONSIDERATION THEREFOR PRIOR TO
          SUCH QUALIFICATION IS UNLAWFUL, UNLESS THE SALE OF SHARES IS EXEMPT
          FROM THE QUALIFICATION BY SECTION 25100, 25102 OR 25105 OF THE
          CALIFORNIA CORPORATIONS CODE.  THE RIGHTS OF ALL PARTIES TO THIS
          SUBSCRIPTION AGREEMENT ARE EXPRESSLY CONDITIONED UPON SUCH
          QUALIFICATION BEING OBTAINED, UNLESS THE SALE IS SO EXEMPT.

     (14) For Residents of Connecticut:

          THESE SHARES HAVE NOT BEEN REGISTERED UNDER SECTION 36-485 OF THE
          CONNECTICUT UNIFORM SECURITIES ACT AND THEREFORE CANNOT BE RESOLD
          UNLESS THEY ARE REGISTERED UNDER SUCH ACT OR UNLESS AN EXEMPTION FROM
          REGISTRATION IS AVAILABLE.  THE SHARES OFFERED HEREBY HAVE NOT BEEN
          APPROVED OR DISAPPROVED BY THE BANKING COMMISSIONER OF THE STATE OF
          CONNECTICUT.  ANY REPRESENTATION TO THE CONTRARY IS UNLAWFUL.

     (15) For Residents of Florida:

          THE SHARES OFFERED HEREBY HAVE NOT BEEN REGISTERED UNDER THE FLORIDA
          SECURITIES ACT (THE "FLORIDA ACT") AND WILL BE OFFERED AND SOLD
          PURSUANT TO AN EXEMPTION UNDER SECTION 517.061 OF THE FLORIDA ACT.
          ALL FLORIDA RESIDENTS SHALL HAVE THE PRIVILEGE OF VOIDING THE PURCHASE
          OF ANY OF THE SHARES WITHIN THREE DAYS AFTER THE FIRST TENDER OF
          CONSIDERATION IS MADE BY SUCH PURCHASER TO THE COMPANIES, AN AGENT OF
          THE COMPANIES, OR AN ESCROW AGENT OR WITHIN THREE DAYS AFTER THE
          AVAILABILITY OF THAT PRIVILEGE IS COMMUNICATED TO SUCH PURCHASER,
          WHICHEVER OCCURS LATER.

                                       -7-

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     (16) For Residents of Georgia:

          THE UNDERSIGNED ACKNOWLEDGES AND UNDERSTANDS (I) THAT THE SHARES
          SUBSCRIBED FOR HEREBY WILL BE ISSUED OR SOLD IN RELIANCE ON PARAGRAPH
          13 OF CODE SECTION 10-5-9 OF THE GEORGIA SECURITIES ACT OF 1973, AND
          MAY NOT BE SOLD OR TRANSFERRED EXCEPT IN A TRANSACTION WHICH IS EXEMPT
          UNDER SUCH ACT OR PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT
          UNDER SUCH ACT AND (II) THAT THE CERTIFICATES REPRESENTING THE SHARES
          SUBSCRIBED FOR HEREBY WILL CONTAIN A LEGEND TO SUCH EFFECT.

     (17) For Residents of Missouri:

          THE UNDERSIGNED ACKNOWLEDGES AND UNDERSTANDS (I) THAT THE SHARES
          SUBSCRIBED FOR HEREBY ARE NOT REGISTERED UNDER THE MISSOURI UNIFORM
          SECURITIES ACT AND MAY BE DISPOSED OF ONLY THROUGH A LICENSED
          BROKER-DEALER AND (II) THAT IT IS A FELONY TO SELL SHARES IN VIOLATION
          OF THE MISSOURI SECURITIES ACT.

     (18) For Residents of New York:

          THIS PRIVATE OFFERING MEMORANDUM HAS NOT BEEN REVIEWED BY THE ATTORNEY
          GENERAL PRIOR TO ITS ISSUANCE AND USE.  THE ATTORNEY GENERAL OF THE
          STATE OF NEW YORK HAS NOT PASSED ON OR ENDORSED THE MERITS OF THIS
          OFFERING.  ANY REPRESENTATION TO THE CONTRARY IS UNLAWFUL.

     (19) For Residents of Pennsylvania:

          EACH PENNSYLVANIA RESIDENT WHO SUBSCRIBES FOR THE SHARES BEING OFFERED
          HEREBY AGREES NOT TO SELL THESE SHARES FOR A PERIOD OF TWELVE MONTHS
          AFTER THE DATE OF PURCHASE.  UNDER PROVISION OF THE PENNSYLVANIA
          SECURITIES ACT OF 1972, EACH PENNSYLVANIA RESIDENT SHALL HAVE THE
          RIGHT TO WITHDRAW HIS OR HER ACCEPTANCE WITHOUT INCURRING ANY
          LIABILITY TO THE ISSUER WITHIN TWO BUSINESS DAYS FROM THE DATE OF
          RECEIPT BY THE COMPANY OF THIS SUBSCRIPTION AGREEMENT.  TO ACCOMPLISH
          THIS WITHDRAWAL A SUBSCRIBER NEED ONLY SEND A LETTER OR TELEGRAM TO
          THE ISSUER AT THE ADDRESS SET FORTH IN THE TEXT HEREOF, INDICATING HIS
          OR HER INTENTION TO WITHDRAW.  SUCH LETTER OR TELEGRAM SHOULD BE SENT
          AND POSTMARKED PRIOR TO THE END OF THE AFOREMENTIONED SECOND BUSINESS
          DAY.  IT IS PRUDENT TO SEND SUCH LETTER BY CERTIFIED MAIL, RETURN
          RECEIPT REQUESTED, TO ENSURE THAT IT IS RECEIVED AND ALSO TO EVIDENCE
          THE TIME WHEN IT WAS MAILED.  IF THE REQUEST IS MADE ORALLY (IN PERSON
          OR BY TELEPHONE, TO THE ISSUER AT THE NUMBER LISTED IN THE TEXT
          HEREOF), A WRITTEN CONFIRMATION THAT THE REQUEST HAS BEEN RECEIVED
          SHOULD BE REQUESTED.

                                       -8-

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D.   REGISTRATION RIGHTS.

     (1)  REGISTRATION OF COMMON SHARES.  Within sixty days from the Closing
          Date, the Company shall use its reasonable best efforts to prepare for
          filing with the Commission, and cause to be declared effective, a
          "shelf" registration statement (the "Shelf Registration") pursuant to
          Rule 415 under the Securities Act providing for the sale by the
          Purchasers of the shares of Common Stock included in the Offering.
          The Company shall use its reasonable best efforts to cause the
          registration statement to be declared effective as soon as practicable
          after it has been filed with the Commission.  The Company agrees to
          use its reasonable best efforts to keep such Shelf Registration
          continuously effective for a period ending on the earliest of (a) the
          fifth anniversary of the effective date of such Shelf Registration,
          (b) the date on which all such Common Stock covered thereby have been
          sold thereunder, or (c) the date upon which all such Common Stock are
          freely transferable without restriction under the Securities Act.  For
          the purpose of this Agreement, "reasonable best efforts" shall mean
          the best efforts of the Company consistent with sound and reasonable
          business practices and judgment.

     (2)  REGISTRATION PROCEDURES.  In connection with the Company's obligations
          with respect to the Shelf Registration, the Company shall use its
          reasonable best efforts to effect the registration in furtherance of
          the sale of the Common Stock by the holders thereof in accordance with
          the intended method or methods of distribution thereof described in
          the Shelf Registration.  In connection therewith, the Company shall,
          as promptly as may be practicable:

               (a)  prepare and file with the Commission a registration
          statement with respect to the Common Stock on any form for which the
          Company then qualifies or which counsel for the Company shall deem
          appropriate and which form shall be available for the disposition of
          the Common Stock in accordance with the intended method or methods of
          disposition thereof;

               (b)  prepare and file with the Commission such amendments and
          supplements to such registration statement and the prospectus used in
          connection therewith as may be necessary to keep such registration
          statement effective for the applicable period specified in Paragraph
          (1) above;

               (c)  furnish to each Purchaser which is selling Common Stock a
          copy of such registration statement, each amendment and supplement
          thereto (in each case including all exhibits thereto but excluding all
          documents incorporated by reference therein unless specifically so
          requested by such Purchaser) and such reasonable number of copies of
          the prospectus included in such registration statement (including each
          preliminary prospectus) as such Purchaser may reasonably request;

               (d)  use reasonable best efforts to register or qualify the
          Common Stock under such other securities laws or blue sky laws of such
          jurisdictions as the Purchasers shall reasonably request, and take any
          and all such actions as may be reasonably necessary or advisable to
          enable the Purchasers to consummate the disposition in such
          jurisdictions of such Common Stock;

                                       -9-

<PAGE>

               (e)  notify each Purchaser, at any time when a prospectus
          relating thereto is required to be delivered under the Securities Act
          within the period that the Company is required to keep the
          registration statement effective, of the happening of any event as a
          result of which the prospectus included in such registration statement
          (as then in effect) contains an untrue statement of a material fact or
          omits to state any material fact required to be stated therein or
          necessary to make the statements therein not misleading.  As promptly
          as practicable following any such occurrence, the Company shall
          prepare and furnish to each Purchaser a reasonable number of copies of
          a supplement or an amendment of such prospectus as may be necessary so
          that, as thereafter delivered to subsequent purchasers of the
          Securities, such prospectus shall meet the requirements of the
          Securities Act and relevant state securities laws, provided that such
          obligation on the part of the Company shall be suspended for such
          period of time as the Company considers reasonably necessary and in
          its best interest due to circumstances then existing (but not more
          than 30 days in any 180-day period).  Each Purchaser shall furnish to
          the Company such information regarding each such Purchaser and its
          proposed method of distribution of the Securities as the Company may
          from time to time request and as shall be required by law to effect
          and maintain the registration of such Securities under the Securities
          Act and any state securities laws;

               (f)  advise each Purchaser, promptly after receiving notice
          thereof, of any stop order issued or threatened by the Commission and
          use its reasonable best efforts to take all actions required to
          prevent the entry of such stop order, or to remove it if entered;

               (g)  use its reasonable best efforts to cause all Common Stock
          including in such registration statement to be listed, by the date of
          the first sale of Common Stock pursuant to such registration
          statement, on each securities exchange on which the Common Stock of
          the Company is then listed or proposed to be listed;

               (h)  furnish to each Purchaser on the effective date of such
          registration statement a signed counterpart, addressed to the
          Purchasers, of (i) an opinion of counsel representing the Company and
          reasonably satisfactory to such Purchasers that the registration
          statement (including each amendment or supplement thereto and
          prospectus included therein) complies as to form in all material
          respects with the requirements of the Securities Act and the
          applicable rules and regulations thereunder, and (ii) a "comfort"
          letter from the independent public accountants retained by the
          Company, stating that they are independent public accountants within
          the meaning of the Securities Act and that, in the opinion of such
          accountants, the financial statements of the Company included or
          incorporated by reference in the registration statement or the
          prospectus, or any amendment or supplement thereof, comply as to form
          in all material respects with the applicable accounting requirements
          of the Securities Act and the published rules and regulations
          thereunder, and covering such other financial matters of the type
          customarily covered by such letters;

               (i)  otherwise use its reasonable best efforts to comply with the
          provisions of the Securities Act with respect to the disposition of
          all of the Common Stock covered by such registration statement in
          accordance with the intended methods of disposition by the Purchasers
          thereof set forth in such registration statement and to make generally
          available to its security holders, as soon as reasonably practicable,
          an earnings statement satisfying the provisions of Section 11(a) of
          the Securities Act and Rule 158 thereunder.

                                      -10-

<PAGE>

     (3)  EXPENSES.  All expenses incident to the Company's performance of or
          compliance with the provisions of this Section D (including, without
          limitation, all registration and filing fees, fees and expenses of
          compliance with securities or blue sky laws, fees and expenses
          incurred in connection with the listing of the Common Stock to be
          registered on each securities exchange on which similar securities
          issued by the Company are then listed, printing expenses, fees and
          disbursements of counsel for the Company, reasonable fees and
          disbursements of one counsel for the Purchasers and fees and
          disbursements of all independent certified public accountants and
          other persons retained by the Company) will be borne by the Company.
          Notwithstanding the foregoing, the Purchasers shall pay any and all
          underwriting fees, discounts or commissions attributable to the sale
          of Common Stock.

     (4)  INDEMNIFICATION.

          (a)  Upon the registration of Common Stock pursuant to Section D(1) of
               this Agreement, and in consideration of the agreements of the
               Purchasers contained herein, the Company shall, and it hereby
               agrees to, indemnify and hold harmless, to the extent permitted
               by law, each of the Purchasers which holds Common Stock to be
               included in such registration, its officers and directors, each
               underwriter of such Common Stock, if any, and each person who
               controls such person (within the meaning of the Securities Act)
               against all losses, claims, damages, liabilities and expenses
               (including reasonable attorneys' fees and expenses) to which such
               Purchaser, its officers, directors, each underwriter, or such
               controlling persons may become subject, insofar as such losses,
               claims, damages, liabilities and expenses (or actions in respect
               thereof) arise out of or are based upon any untrue statement or
               alleged untrue statement of material fact contained in any such
               registration statement, any prospectus or preliminary prospectus
               contained therein or any amendment or supplement thereto, or any
               omission or alleged omission to state therein a material fact
               required to be stated therein or necessary to make the statements
               therein not misleading, and will reimburse each such Purchaser,
               each such underwriter and each such controlling person for any
               legal or other expenses reasonably incurred by them in connection
               with investigating or defending any such loss, claim, damage,
               liability or action; except (i) insofar as the same arise out of
               or are based upon an untrue statement or omission or alleged
               omission so made based upon information furnished by such
               Purchaser, underwriter or controlling person in writing
               specifically for use in such registration statement or prospectus
               or (ii) insofar as the same are caused by such Purchaser's or
               such underwriter's failure to deliver a copy of such registration
               statement or prospectus or any amendments or supplements thereto
               after the Company has furnished such Purchaser or such
               underwriter with a sufficient number of copies of the same; and
               provided, however, that the foregoing indemnity and reimbursement
               obligation shall not be applicable to the extent that any such
               loss, claim, damage, liability or action arises out of or is
               based on any untrue statement or omission made in:  (i) a
               preliminary prospectus, which untrue statement or omission is
               corrected in the final prospectus and such final prospectus is
               made available to such Purchaser in accordance with the
               requirements of Rule 424 under the Securities Act; or (ii) any
               prospectus, which untrue statement or omission is corrected in a
               prospectus supplement or amended prospectus and such prospectus
               supplement or amended prospectus is made available to such
               Purchaser prior to the sale of Common Stock which gave rise to
               such loss, claim, damage, liability or expense.

                                     -11-

<PAGE>

          (b)  In connection with any registration statement under which Common
               Stock are registered under the Securities Act and pursuant to
               which a Purchaser offers and sells Common Stock, each such
               Purchaser shall, and it hereby agrees to, indemnify and hold
               harmless, to the extent permitted by law, each of the Company,
               its officers and directors, and each person who controls the
               Company (within the meaning of the Securities Act) and, if the
               offering is an underwritten offering, the underwriters, against
               all losses, claims, damages, liabilities and expenses (including
               reasonable attorneys' fees and expenses) to which the Company,
               its officers and directors, underwriters, or controlling persons
               may become subject, insofar as such losses, claims, damages,
               liabilities and expenses (or actions in respect thereof) arise
               out of or are based upon any untrue statement or alleged untrue
               statement of material fact contained in any such registration
               statement, any prospectus or preliminary prospectus contained
               therein or any amendment or supplement thereto, or any omission
               or alleged omission to state therein a material fact required to
               be stated therein or necessary to make the statements therein not
               misleading and will reimburse the Company and each such officer,
               director, underwriter and controlling person for any legal or
               other expenses reasonably incurred by them in connection with
               investigating or defending any such loss, claim, damage,
               liability or action, insofar as (i) the same arise out of or are
               based upon any untrue statement or omission or alleged omission
               so made based upon information furnished by such Purchaser or
               controlling person of such Purchaser, in writing specifically for
               use in such registration statement or prospectus or (ii) the same
               are caused by such Purchaser's failure to deliver a copy of such
               registration statement or prospectus or any amendments or
               supplements thereto after the Company has furnished such
               Purchaser with a sufficient number of copies of the same and
               provided, further, that the liability of each Purchaser under
               this Paragraph 4(b) shall be limited to the proportion of any
               such loss, claim, damage, liability or expense which is equal to
               the proportion that the public offering price of Common Stock
               sold by such Purchaser under such registration statement bears to
               the total public offering price of all securities sold
               thereunder, but not to exceed the amount of the proceeds received
               by such Purchaser from the sale of the Common Stock covered by
               such registration statement.

          (c)  Any person entitled to indemnification hereunder will (i) give
               prompt notice to the indemnifying party of any claim with respect
               to which it seeks indemnification (but the failure to give such
               notice will not affect the right to indemnification hereunder,
               unless the indemnifying party is materially prejudiced by such
               failure) and (ii) unless in such indemnified party's reasonable
               judgment a conflict of interest may exist between such
               indemnified and indemnifying parties with respect to such claim,
               permit such indemnifying party to assume the defense of such
               claim with counsel selected by the indemnifying party and
               reasonably satisfactory to the indemnified party.  If such
               defense is not assumed by the indemnifying party or if the
               indemnifying party is not permitted to assume such defense then
               (x) the indemnified party shall select counsel, which counsel
               must be reasonably satisfactory to the indemnifying party and (y)
               the indemnifying party will not be subject to any liability for
               any settlement made without its consent (which consent will not
               be unreasonably withheld).  No indemnifying party will consent to
               entry of any judgment or enter into any settlement which does not
               include as an unconditional term thereof the giving by the
               claimant or plaintiff to such

                                      -12-

<PAGE>

               indemnified party of a release from all liability in respect of
               such claim or litigation.  An indemnifying party who is not
               entitled to, or elects not to, assume the defense of a claim
               will not be obligated to pay the fees and expenses of more than
               one counsel for all parties indemnified by such indemnifying
               party with respect to such claim, unless in the reasonably
               judgment of any indemnified party a conflict of interest may
               exist between such indemnified party and any other of such
               indemnified parties with respect to such claim, in which case
               the indemnifying party shall be obligated to pay the fees and
               expenses of one additional counsel, who must be reasonably
               satisfactory to the indemnifying party.

          (d)  Each party hereto agrees that, if for any reason the
               indemnification provisions contemplated by Paragraph 4(a) or
               Paragraph 4(b) are unavailable or are insufficient to hold
               harmless an indemnified party in respect of any losses, claims,
               damages, liabilities or expenses (or actions in respect thereof)
               referred to therein, then each indemnifying party shall
               contribute to the amount paid or payable by such indemnified
               party as a result of such losses, claims, damages, liabilities or
               expenses (or actions in respect thereof) in such proportion as is
               appropriate to reflect the relative fault of the indemnifying
               party and the indemnified party as well as any other relevant
               equitable considerations.  The relative fault of such
               indemnifying party and indemnified party shall be determined by
               reference to, among other things, whether the untrue or alleged
               untrue statement of a material fact or omission or alleged
               omission to state a material fact relates to information supplied
               by such indemnifying party or indemnified party, and the parties'
               relative intent, knowledge, access to information and opportunity
               to correct or prevent such statement or omission.  The parties
               hereto agree that it would not be just and equitable if
               contribution pursuant to this Paragraph 4(d) were determined by
               pro rata allocation (even if the Purchasers or any underwriters
               or all of them were treated as one entity for such purpose) or by
               any other method of allocation which does not take into account
               the equitable considerations referred to in this Paragraph 4(d).
               No person guilty of fraudulent misrepresentation (within the
               meaning of Section 11(f) of the Securities Act) shall be entitled
               to contribution from any person who was not guilty of such
               fraudulent misrepresentation.

          (e)  The indemnification and contribution obligations and each other
               provision set forth in this Paragraph 4 shall remain in full
               force and effect regardless of any investigation made by or on
               behalf of the Company, any Purchaser, any officer or employee of
               the Company or such Purchaser, any underwriter, any officer or
               employee of such underwriter, or any controlling person of any of
               the foregoing and shall survive the transfer and registration of
               Common Stock by such Purchaser.

     (5)  RULE 144 REPORTING.  With a view to making available to Purchasers the
          benefits of Rule 144 promulgated by the Commission under the
          Securities Act, the Company agrees to use its reasonable best efforts
          to:

          (a)  make and keep adequate current public information with respect to
               the Company available, as those terms are used in Rule 144 under
               the Securities Act, at all times after the Final Closing Date;

                                     -13-

<PAGE>

          (b)  file with the Commission in a timely manner all reports and other
               documents required of the Company under the Exchange Act; and

          (c)  furnish to Purchasers promptly upon request a written statement
               by the Company as to its compliance with the reporting
               requirements of Rule 144 and the Exchange Act, a copy of the most
               recent annual or quarterly report of the Company, and such other
               reports and documents of the Company as any Purchaser may
               reasonably request in order to permit such Purchaser to avail
               itself of any rule or regulation of the Commission allowing such
               Purchaser to sell its Common Stock without registration.

     (6)  AMENDMENTS AND WAIVERS.  Any provision of this Section D may be
          amended or waived if, but only if, in the case of an amendment, such
          amendment is in writing and is signed by the Company and the
          Purchasers who are the holders of a majority of the Common Stock or,
          in the case of a waiver, such waiver is in writing and is signed by
          the party to be charged with having granted such waiver.  No failure
          or delay by the Company or any Purchaser in exercising any right,
          power or privilege hereunder shall operate as a waiver thereof, nor
          shall any single or partial exercise thereof preclude any other or
          further exercise thereof or the exercise of any other right, power or
          privilege.

E.   MISCELLANEOUS

     (1)  All pronouns and any variations thereof used herein shall be deemed to
          refer to the masculine, feminine, singular or plural, as the identity
          of the person or persons may require.

     (2)  Except as set forth in Section A(4) herein, neither this Agreement nor
          any provision hereof shall be waived, modified, changed, discharged,
          terminated, revoked or canceled except by an instrument in writing
          signed by the party effecting the same against whom any change,
          discharge or termination is sought.

     (3)  Notices required or permitted to be given hereunder shall be in
          writing and shall be deemed to be sufficiently given when personally
          delivered or sent by registered mail, return receipt requested,
          addressed:  (i) if to the Company, to Energy BioSystems Corporation,
          4200 Research Forest Drive, The Woodlands, Texas 77381, Attention:
          Paul G. Brown, III, or (ii) if to the undersigned, to the address for
          correspondence set forth in the Subscription Agreement, or at such
          other address as may have been specified by written notice given in
          accordance with this Paragraph (3).

     (4)  Failure of the Company to exercise any right or remedy under this
          Agreement or any other agreement between the Company and the
          undersigned, or otherwise, or delay by the Company in exercising such
          right or remedy, will not operate as a waiver thereof.  No waiver by
          the Company will be effective unless and until it is in writing and
          signed by the Company.

     (5)  This Agreement shall be enforced, governed and construed in all
          respects in accordance with the laws of the State of Texas, as such
          laws are applied by the Texas courts to agreements entered into and to
          be performed in Texas by and between residents of Texas, and shall be
          binding upon the undersigned, the undersigned's heirs, estate, legal
          representatives, successors and assigns and shall inure to the benefit
          of the Company, its

                                       -14-

<PAGE>

          successors and assigns.  If any provision of this Subscription
          Agreement is invalid or unenforceable under any applicable statute
          or rule of law, then such provision shall be deemed modified to
          conform with such statute or rule of law.  Any provision hereof
          that may prove invalid or unenforceable under any law shall not
          affect the validity or enforceability of any other provisions hereof.

     (6)  This Agreement constitutes the entire agreement between the parties
          hereto with respect to the subject matter hereof and may be amended
          only by writing executed by both parties hereto.

     (7)  Each party hereto has had the opportunity to review this Agreement
          with its separate legal counsel.

F.   SIGNATURE

The signature of this Agreement is contained as part of the applicable
subscription package, entitled "Signature Page".








                                      -15-

<PAGE>

                          ENERGY BIOSYSTEMS CORPORATION
                              REVISED SIGNATURE PAGE

The undersigned hereby subscribes for the number of Shares as set forth below.

1.   Dated:  ____________________, 19___

2.   Number of Shares subscribed for:  ____________________

3.   Fill in A if you elect to purchase the Shares at $2.00 per Share with the
     Warrants.
     Fill in B if you elect to purchase the Shares at $1.80 per Share without
     any Warrants.

     A.   Aggregate purchase price for number of Shares (with
          Warrants) subscribed for, at $2.00 per Share
                    $____________________

     B.   Aggregate purchase price for number of Shares (without Warrants)
          subscribed for, at $1.80 per Share
                    $____________________



-----------------------------------     --------------------------------------
Signature of Subscriber                 Taxpayer Identification or Social
(and title, if applicable)              Security Number

-----------------------------------     --------------------------------------
Signature of Joint Purchaser            Taxpayer Identification or Social
(if any)                                Security Number

-----------------------------------     --------------------------------------
Name and Residence Address              Mailing Address
(Post Office Address Not Acceptable)    (if different from Residence Address)

-----------------------------------     --------------------------------------
Name (please print as name will appear  Name (please print)
on certificate)

-----------------------------------     --------------------------------------
Number and Street                       Number and Street

-----------------------------------     --------------------------------------
City State          Zip Code            City State          Zip Code


ACCEPTED BY:                            ENERGY BIOSYSTEMS CORPORATION


Dated:                                  By:
-----------------------------------        -----------------------------------
                                               President and CEO


<PAGE>

                              PURCHASER QUESTIONNAIRE



Energy BioSystems
4200 Research Forest Drive
The Woodlands, Texas  77381

Attention: President

Re:  Purchase of Shares of Common Stock

Ladies & Gentlemen:

          The information contained herein is being furnished to Energy
BioSystems Corporation, a Delaware corporation, (the "Company") in connection
with the purchase of Common Stock of the Company by the undersigned to assure
the Company that the undersigned will meet the suitability standards for
potential investors for purposes of federal and state securities laws, and to
assure that the offer and sale of such securities by the Company may be made to
the undersigned without registration under the Securities Act of 1933, as
amended (the "Act"), and applicable state securities laws.

          The undersigned represents to the Company that (i) the information and
representations contained herein are complete and accurate and may be relied
upon by the Company and (ii) the undersigned will notify the Company immediately
of any material change in any of such information occurring prior to the closing
of the purchase of the Securities by the undersigned.  All information furnished
is for the sole use of the Company and their counsel and will be held in
confidence, except that this Questionnaire may be furnished to such parties as
is necessary to establish compliance with federal or state securities laws.

PLEASE COMPLETE ALL OF THE FOLLOWING QUESTIONS (1-10), SIGN AND DATE AND RETURN
TO THE CORPORATION.




                                       -2-

<PAGE>

                    ALL INFORMATION WILL BE TREATED CONFIDENTIALLY

1.   Name of Entity or Individual:____________________________________________

     Business Address: _______________________________________________________

     City:_________________________ State:__________________  Zip:____________

     Telephone:____________________

     Taxpayer Identification No. or Social Security No.:______________________


2.   (ANSWER ONLY IF AN INDIVIDUAL)

     (a)  Principal Residence Address:________________________________________

          City:____________________ State:___________________  Zip:___________

          Telephone:_______________


          Communications should be sent to (check one)

          ___________________ business address or________________ home address.


     (b)  Date of Birth:________________ U.S. Citizen:  Yes_______  No ________

          College:___________________ Degree:_________________ Year:___________

          Graduate School:______________ Degree:______________ Year:___________

          Other Education:_____________________________________________________

     (c)  Employment and Nature of Business:___________________________________

          _____________________________________________________________________

          Position and Duties:_________________________________________________

          _____________________________________________________________________

          Any other Prior Occupations or Duties during Past Five Years:

          _____________________________________________________________________

          _____________________________________________________________________

          _____________________________________________________________________

          _____________________________________________________________________

          _____________________________________________________________________

                                      -3-

<PAGE>


     (d)  Income from all sources before this investment is in excess of
          $_____________ (exclusive of any income attributable to your spouse)
          for each of the undersigned's two previous tax years and estimated to
          be in excess of $_______________ (exclusive of any income attributable
          to your spouse) for the undersigned's current tax year.

     (e)  The undersigned's personal net worth (excluding the proposed
          investment in the Shares) is in excess of $_______________.

     (f)  The undersigned understands the full nature and risk of this
          investment.
          ________ Yes_______ No

     (g)  The undersigned believes the undersigned can afford the complete loss
          of the investment.________ Yes_______ No

     (h)  This investment constitutes less than ten percent (10%) of the
          undersigned's net worth.________ Yes_______ No

3.   (ANSWER ONLY IF A CORPORATION, PARTNERSHIP, TRUST OR OTHER ENTITY)

     (a)  Form of Organization:________________________________________________

     (b)  Jurisdiction of Incorporation or Formation:__________________________

     (c)  Address of principal place of business:

          _____________________________________________________________________

          _____________________________________________________________________

          _____________________________________________________________________

     (d)  Date of Incorporation or Formation:__________________________________

     (e)  Nature of Business:__________________________________________________

          _____________________________________________________________________

     (f)  Names of Directors if a Corporation, of Partners (together with the
          address of each Partner) if a Partnership, of Trustees if a Trust, of
          Joint Venturers if a Joint Venture:

          _____________________________________________________________________

          _____________________________________________________________________

          _____________________________________________________________________

          _____________________________________________________________________

          _____________________________________________________________________


                                       -4-

<PAGE>

     (g)  The persons named in Section 3(f) above understand the full nature and
          risk of this investment.________ Yes_______ No

     (h)  The undersigned can afford the complete loss of the investment.
          ________ Yes_______ No

     (i)  The undersigned's net income before this investment is in excess of
          $ __________________ for the undersigned's two previous tax years and
          estimated to be in excess of $_________________ for the undersigned's
          current tax year.

     (j)  The undersigned's total assets (excluding the proposed investment  in
          the  Shares) is in excess of $_________________ .

     (k)  Was the undersigned formed or organized for the specific purpose of
          acquiring the Shares?________ Yes_______ No

4.   The undersigned is an experienced and sophisticated investor.________ Yes
     ________ No

5.   The undersigned has invested in excess of $________________ over the past
     five years.

6.   Please state below the types of investments the undersigned has made in the
     past five years, with particular attention to investments in nonmarketable
     investments.  Include amount invested in each type of investment.
     __________________________________________________________________________

     __________________________________________________________________________

     __________________________________________________________________________

     __________________________________________________________________________

7.   Please state below any additional information which the undersigned thinks
     qualifies the undersigned to evaluate the merits and risks of this
     investment.
     __________________________________________________________________________

     __________________________________________________________________________

     __________________________________________________________________________

     __________________________________________________________________________

8.   The undersigned will have an attorney, accountant, or other consultant
     review this investment as the undersigned may require for a full
     understanding of the investment and the risk involved.
     _______ Yes _______ No

9.   The undersigned will have a representative, who has such knowledge and
     experience in business and financial matters and is capable of evaluating
     the merits and risks of this investment, make the investment decision on
     behalf of the undersigned with respect to the Shares.
     _______ Yes _______ No

10.  The undersigned (or in the case of a corporation, partnership, trust or
     other entity, either such entity or each person named in Section 3(f)
     hereof) is an "accredited investor", as such term is defined by Regulation
     D ("Regulation D") promulgated under the Act within the meaning of one of
     the categories described in Schedule I attached thereto.
     _______ Yes _______ No


                                      -5-

<PAGE>

     Please specify the category or categories of qualification:

     __________________________________________________________________________

                                          Name:________________________________


Dated:_____________________ , 1999        By:__________________________________


                                          Title:_______________________________

                                          _____________________________________
                                          (Please Type or Print Name)


NAME OF PARTNERSHIP, CORPORATION,
TRUST, ESTATE OR OTHER ENTITY
(IF APPLICABLE):

___________________________________


TITLE OF PERSON SIGNING ON
BEHALF OF SUCH ENTITY:

___________________________________




                                      -6-

<PAGE>

                                      SCHEDULE I


          An "accredited investor" includes ANY of the following:

          (a)  An individual with net worth (including principal residence) or,
     together with his or her spouse, JOINT net worth in EXCESS of $1,000,000;

          (b)  An individual who had an income in EXCESS of $200,000 for each of
     the two most recent years or joint income with such individual's spouse in
     excess of $300,000 in each of those years AND who reasonably expects to
     reach the same income level in the current year;

          (c)  Any of certain institutional investors, including:

               (1)  a state or national bank as defined in 3(a)(2) of the Act,
          or savings and loan association or other institution defined in
          section 3(a)(5) of the Act (whether acting in an individual or
          fiduciary capacity);

               (2)  an insurance company as defined in section 2(13) of the Act;

               (3)  an investment company registered under the Investment
          Company Act of 1940;

               (4)  a business development company as defined in section 2(a)48
          of the Act;

               (5)  a Small Business Investment Company licensed by the U.S.
          Small Business Administration under section 301(c) or (d) of the Small
          Business Investment Act of 1958;

               (6)  an ERISA employee benefit plan where (i) the investment
          decision is made by a plan fiduciary which is a bank, insurance
          company or registered investment advisor, OR (ii) the employee benefit
          plan has total assets IN EXCESS OF $5,000,000 or, if a self-directed
          plan, with investment decisions made solely by persons that are
          accredited investors;

               (7)  an Internal Revenue Code 501(c)(3) organization, a
          corporation, a Massachusetts or similar business trust or partnership,
          not formed for the specific purpose of purchasing the Shares, with
          total assets IN EXCESS OF $5,000,000;

          (d)  Any director, executive officer or general partner of the issuer
     of  the  Shares being  offered or  sold  or  any director, executive
     officer, or general partner of a general partner of that issuer;

          (e)  Any legal entity (corporation, partnership, etc.) WHOLLY owned by
     persons or entities who are themselves accredited investors.

          (f)  A trust, with total assets in excess of $5,000,000, not formed
     for the specific purpose of acquiring the Shares offered, whose purchase is
     directed by a "sophisticated person" as defined by Regulation D.

                                     -7-