Document:

EXHIBIT 4.5

                              AMENDED AND RESTATED

                                   BY-LAWS OF

                               ENZO BIOCHEM, INC.

                            (A NEW YORK CORPORATION)

                                    ARTICLE I

                             MEETING OF SHAREHOLDERS

          Section 1. ANNUAL MEETING.  The annual meeting of the  shareholders of
Enzo Biochem,  Inc.,  (hereinafter called the "Corporation") for the election of
directors and for the  transaction of such other business as may come before the
meeting  shall be held on the third  Wednesday of the fifth month  following the
close of the Corporation's  fiscal year, if not a legal holiday,  and if a legal
holiday,  then on the next  succeeding day not a legal holiday,  at such time as
shall be designated by the Board or Chairman of the Board or the  President.  If
the annual  meeting shall not be held on the day  hereinabove  provided for, the
Board shall call a special meeting for the election of directors,  which meeting
shall be held within two months after said day.

          Section 2. SPECIAL MEETINGS.  Except as otherwise  required by law and
subject  to the rights of the  holders of any class or series of stock  having a
preference  over  another  class or  series  of stock  as to  dividends  or upon
liquidation,  special  meetings of shareholders of the Corporation may be called
only by the Board pursuant to a resolution  approved by a majority of the entire
Board  (whether  or not  there  exist any  vacancies  in  previously  authorized
directorships  at the time any such  resolution  is  presented  to the Board for
adoption).

          Section 3. NOTICE OF MEETINGS.  Notice of the place,  date and time of
the holding of each annual and special meeting of the  shareholders  and, in the
case of a special  meeting,  the  purpose or  purposes  thereof,  shall be given
personally or by mail in a postage prepaid envelope to each shareholder entitled
to vote at such  meeting,  not less than ten nor more than fifty days before the
date of such meeting,  and, if mailed,  it shall be directed to such shareholder
at his address as it appears on the records of the Corporation,  unless he shall
have filed with the Secretary of the Corporation, a written request that notices
to him be mailed to some other  address,  in which case, it shall be directed to
him at such other address.  Notice of any meeting of  shareholders  shall not be
required to be given to any  shareholder who shall attend such meeting in person
or by proxy and shall  not,  at the  beginning  of such  meeting,  object to the
transaction  of any  business  because  the  meeting is not  lawfully  called or
convened,  or who shall,  either  before or after the  meeting,  submit a signed
waiver of notice,  in person or by proxy.  Unless the Board  shall fix after the
adjournment a new record date for an adjourned meeting, notice of such adjourned
meeting  need not be given if the time and place to which the  meeting  shall be
adjourned  were announced at the meeting at which the  adjournment is taken.  At
the adjourned meeting the Corporation may transact any business which might have
been  transacted at the original  meeting.  If the  adjournment is for more than
thirty  days,  or if after the  adjournment  a new record  date is fixed for

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the adjourned  meeting, a notice of the adjourned meeting shall be given to each
shareholder of record entitled to vote at the meeting.

          Section 4. PLACE OF MEETINGS. Meetings of the shareholders may be held
at such  place,  within or without the State of  incorporation,  as the Board or
other officer  calling the same shall specify in the notice of such meeting,  or
in a duly executed waiver of notice thereof.

          Section 5. QUORUM.  At all meetings of the shareholders the holders of
a  majority  of the votes of the shares of stock of the  Corporation  issued and
outstanding  and  entitled  to vote  shall be  present  in person or by proxy to
constitute  a  quorum  for  the   transaction  of  any  business,   except  when
shareholders  are  required  to vote by class,  in which event a majority of the
issued  and  outstanding  shares of the  appropriate  class  shall be present in
person  or by proxy,  or  except as  otherwise  provided  by  statute  or in the
Certificate  of  Incorporation.  In the  absence of a quorum,  the  holders of a
majority  of the votes of the shares of stock  present in person or by proxy and
entitled to vote,  or if no  shareholder  entitled to vote is present,  then any
officer of the  Corporation  may adjourn the meeting  from time to time.  At any
such  adjourned  meeting at which a quorum may be present  any  business  may be
transacted which might have been transacted at the meeting as originally called.

          Section  6.  ORGANIZATION.  At each  meeting of the  shareholders  the
Chairman of the Board, or in his absence or inability to act, the President,  or
in the  absence  or  inability  to act of the  Chairman  of the  Board  and  the
President,  a Vice  President,  or in the absence of all of the  foregoing,  any
person chose by a majority of those shareholders present,  shall act as chairman
of the  meeting.  The  Secretary,  or, in his absence or  inability  to act, the
Assistant  Secretary  or any person  appointed  by the  chairman of the meeting,
shall act as secretary of the meeting and keep the minutes thereof.

          Section 7. ORDER OF BUSINESS. The order of business at all meetings of
the shareholders shall be as determined by the chairman of the meeting.

          Section 8.  VOTING.  Except as  otherwise  provided  by  statute,  the
Certificate of Incorporation, or any certificate duly filed in the office of the
Department  of State of the  State of  incorporation,  each  holder of record of
shares of stock of the Corporation having voting power shall be entitled at each
meeting of the  shareholders  to one vote for every share of such stock standing
in his name on the record of  shareholders  of the Corporation on the date fixed
by the Board as the record date for the  determination  of the  shareholders who
shall be  entitled to notice of and to vote at such  meeting;  or if such record
date shall not have been so fixed, then at the close of business on the day next
preceding  the day on which  notice  thereof  shall be  given,  or if  notice is
waived,  at the close of business on the day next preceding the day on which the
meeting is held;  or each  shareholder  entitled  to vote at any  meeting of the
shareholders  may authorize  another person or persons to act for him by a proxy
signed by such  shareholder  or his  attorney-in-fact.  Any such proxy  shall be
delivered to the secretary of such meeting at or prior to the time designated in
the order of business for so delivering  such  proxies.  No proxy shall be valid
after the  expiration  of three years from the date  thereof,  unless  otherwise
provided in the proxy.  Every proxy shall be  revocable  at the  pleasure of the
shareholder  executing it, except in those cases where an  irrevocable  proxy is
permitted by law. Except as otherwise provided by statute, these By-Laws, or the
Certificate of  Incorporation,  any corporate  action to be taken by vote of the

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shareholders  shall be  authorized  by a majority  of the total  votes,  or when
shareholders  are  required  to vote by class by a majority  of the votes of the
appropriate  class,  cast at a meeting of  shareholders by the holders of shares
present in person or  represented  by proxy and entitled to vote on such action.
Unless  required by statute,  or determined by the chairman of the meeting to be
advisable,  the vote on any question need not be by written ballot. On a vote by
written ballot, each ballot shall be signed by the shareholder voting, or by his
proxy, if there be such proxy, and shall state the number of shares voted.

          Section 9. LIST OF  SHAREHOLDERS.  The  officer  who has charge of the
stock  ledger of the  Corporation,  or the transfer  agent of the  Corporation's
stock,  if there be one then acting,  shall  prepare and make, at least ten days
before  every  meeting  of  shareholders,  a complete  list of the  shareholders
entitled to vote at the meeting, arranged in alphabetical order, and showing the
address of each  shareholder and the number of shares  registered in the name of
each shareholder. Such list shall be open to the examination of any shareholder,
for any purpose germane to the meeting,  during ordinary  business hours,  for a
period of at least ten days prior to the  meeting,  either at a place within the
city where the  meeting is to be held,  at the place  where the meeting is to be
held,  or at the office of the transfer  agent.  The list shall also be produced
and kept at the time and place of the meeting during the whole time thereof, and
may be inspected by any shareholder who is present.

          Section  10.  INSPECTORS.  The Board may, in advance of any meeting of
shareholders,  appoint  one or more  inspectors  to act at such  meeting  or any
adjournment  thereof If the  inspectors  shall not be so  appointed or if any of
them shall fail to appear or act,  the  chairman of the meeting  may, and on the
request of any shareholder  entitled to vote thereat shall,  appoint inspectors.
Each inspector, before entering upon the discharge of his duties, shall take and
sign an oath  faithfully to execute the duties of inspector at such meeting with
strict  impartiality  and according to the best of his ability.  The  inspectors
shall  determine the number of shares  outstanding and the voting power of each,
the number of shares represented at the meeting,  the existence of a quorum, the
validity and effect of proxies,  and shall receive  votes,  ballots or consents,
hear and determine all challenges and questions  arising in connection  with the
right to vote, count and tabulate all votes, ballots or consents,  determine the
result,  and do such acts as are proper to  conduct  the  election  or vote with
fairness to all  shareholders.  On request of the chairman of the meeting or any
shareholder  entitled to vote  thereat,  the  inspectors  shall make a report in
writing of any challenge, request or matter determined by them and shall execute
a certificate of any fact found by them. No director or candidate for the office
of director shall act as inspector or an election of directors.  Inspectors need
not be shareholders.

          Section 11. CONSENT OF SHAREHOLDERS IN LIEU OF MEETING.  To the extent
permitted by law, the meeting and vote of shareholders  can be dispensed with if
all of the  shareholders who would have been entitled to vote upon the action if
such meeting were held shall consent in writing to such  corporate  action being
taken.

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                                   ARTICLE II

                               BOARD OF DIRECTORS

          Section 1. GENERAL POWERS. The business and affairs of the Corporation
shall be managed by the Board.  The Board may  exercise all such  authority  and
powers of the  Corporation  and do all such lawful acts and things as are not by
statute or the Certificate of Incorporation directed or required to be exercised
or done by the shareholders.

          Section 2. ELECTION AND TERMS. The directors, other than those who may
be elected by the  holders of any class or series of stock  having a  preference
over another class or series of stock as to dividends or upon liquidation, shall
be  classified,  with respect to the time for which they  severally hold office,
into three classes, as nearly equal in number as possible,  as determined by the
Board,  one class to be  originally  elected  for a term  expiring at the annual
meeting  of  shareholders  to be held in 1989,  another  class to be  originally
elected for a term expiring at the annual meeting of  shareholders to be held in
1990,  and another  class to be  originally  elected for a term  expiring at the
annual  meeting  of  shareholders  to be held in 1991,  with each  class to hold
office until its successor is elected and  qualified.  At each annual meeting of
the  shareholders of the  Corporation,  the successors of the class of directors
whose term  expires at the  meeting  shall be elected to hold  office for a term
expiring at the annual meeting of shareholders  held in the third year following
the year of their election.

          Section 3.  PLACE OF  MEETINGS.  Meetings  of the Board may be held at
such place, within or without the State of incorporation,  as the Board may from
time to time  determine  or as shall be  specified  in the  notice  or waiver of
notice of such meeting.

          Section 4.  ANNUAL  MEETING.  The Board  shall meet for the purpose of
organization, the election of officers and the transaction of other business, as
soon as practicable after each annual meeting of the  shareholders,  on the same
day and at the same place where such  annual  meeting  shall be held.  Notice of
such  meeting  need not be given.  Such meeting may be held at any other time or
place (within or without the State of incorporation) which shall be specified in
a notice thereof given as hereinafter provided in Section 7 of this Article II.

          Section 5. REGULAR  MEETINGS.  Regular  meetings of the Board shall be
held at such time and place as the Board may from time to time determine. If any
day fixed for a regular  meeting shall be a legal holiday at the place where the
meeting is to be held,  then the meeting  which would  otherwise be held on that
day shall be held at the same hour on the next  succeeding  business day. Notice
of regular meetings of the Board need not be given except as otherwise  required
by statute or these By-Laws.

          Section 6.  SPECIAL  MEETINGS.  Special  meetings  of the Board may be
called by two or more  directors  of the  Corporation  or by the Chairman of the
Board or the President.

          Section 7. NOTICE OF MEETINGS.  Notice of each special  meeting of the
Board (and of each regular  meeting for which notice shall be required) shall be
given by the  Secretary  as  hereinafter  provided  in this  Section 7, in which
notice  shall be  stated  the time and place  (within  or  without

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the State of incorporation) of the meeting. Notice of each such meeting shall be
delivered to each director either personally or by telephone,  telegraph,  cable
or wireless, at least twenty-four hours before the time at which such meeting is
to be held or by  first-class  mail,  postage  prepaid,  addressed to him at his
residence,  or usual  place of  business,  at least three days before the day on
which such  meeting is to be held.  Notice of any such meeting need not be given
to any director who shall,  either before or after the meeting,  submit a signed
waiver of notice or who shall attend such meeting without  protesting,  prior to
or at its  commencement,  the  lack  of  notice  to  him.  Except  as  otherwise
specifically  required  by these  By-Laws,  a notice  or waiver of notice of any
regular or special meeting need not state the purpose of such meeting.

          Section 8. QUORUM AND MANNER OF ACTING. A majority of the entire Board
shall be present in person at any meeting of the Board in order to  constitute a
quorum for the transaction of business at such meeting, and, except as otherwise
expressly required by statute or the Certificate of Incorporation,  the act of a
majority  of the  directors  present at any meeting at which a quorum is present
shall be the act of the Board.  In the absence of a quorum at any meeting of the
Board,  a majority  of the  directors  present  thereat,  or if no  director  be
present,  the Secretary,  may adjourn such meeting to another time and place, or
such meeting, unless it be the annual meeting of the Board, need not be held. At
any  adjourned  meeting  at which a  quorum  is  present,  any  business  may be
transacted which might have been transacted at the meeting as originally called.
Except as provided in Article III of these By-Laws, the directors shall act only
as a Board and the individual directors shall have no power as such.

          Section 9. ORGANIZATION. At each meeting of the Board, the Chairman of
the Board (or, in his absence or  inability to act,  the  President,  or, in his
absence or  inability  to act,  another  director  chosen by a  majority  of the
directors present) shall act as chairman of the meeting and preside thereat. The
Secretary  (or, in his absence or inability to act, any person  appointed by the
chairman) shall act as secretary of the meeting and keep the minutes thereof.

          Section 10.  RESIGNATIONS.  Any director of the Corporation may resign
at any time by giving written notice of his resignation to the Board or Chairman
of the Board or the President or the Secretary.  Any such resignation shall take
effect at the time  specified  therein,  or,  if the time  when it shall  become
effective shall not be specified  therein,  immediately  upon its receipt;  and,
unless otherwise specified therein, the acceptance of such resignation shall not
be necessary to make it effective.

          Section 11.  NEWLY  CREATED  DIRECTORSHIPS  AND  VACANCIES.  Except as
otherwise provided for or fixed by or pursuant to the provisions of Article 4 of
the  Certificate of  Incorporation  relating to the rights of the holders of any
class or series of stock  having a preference  over  another  class or series of
stock as to dividends or upon  liquidation to elect  directors  under  specified
circumstances,  newly created  directorships  resulting from any increase in the
number of  directors  and any  vacancies  on the  Board  resulting  from  death,
resignation,  disqualification,  removal or other  cause  shall be filled by the
affirmative vote of a majority of the remaining  directors then in office,  even
though less than a quorum of the Board.  Any director elected in accordance with
the preceding  sentence  shall hold office for the remainder of the full term of
the class of directors in which the new  directorship was created or the vacancy
occurred  and until  such  director's  successor  shall  have been  elected  and
qualified.  No decrease in the number of directors  constituting the Board shall
shorten the term of any incumbent director.

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          Section 12.  REMOVAL OF DIRECTORS.  Subject to the rights of any class
or series of stock having a preference  over another class or series of stock as
to  dividends  or  upon   liquidation  to  elect   directors   under   specified
circumstances, any director may be removed from office, only with cause and only
by the  affirmative  vote of (i) the holders of 80% of the combined voting power
of the then  outstanding  shares  of stock  entitled  to vote  generally  in the
election of directors,  voting together as a single class and (ii) a majority of
such shares  beneficially owned by the persons not affiliated with an Interested
Shareholder (as defined in Article 14 of the Certificate of Incorporation).

          Section 13.  COMPENSATION.  The Board shall have  authority to fix the
compensation,  including fees and  reimbursement  of expenses,  of directors for
services to the  Corporation  in any  capacity,  provided no such payment  shall
preclude any director  from serving the  Corporation  in any other  capacity and
receiving compensation therefore.

          Section  14.  ACTION BY THE  BOARD.  Any member of the Board or of any
Committee thereof may participate in a meeting of the Board or such committee by
means of a conference telephone or similar communications equipment allowing all
persons  participating  in the  meeting  to hear each of them at the same  time.
Participation by such means shall constitute presence in person at a meeting. To
the extent  permitted under the laws of the State of  incorporation,  any action
required  or  permitted  to be  taken  at any  meeting  of the  Board  or of any
committee  thereof may be taken without a meeting if all members of the Board or
committee,  as the case may be, consent  thereto in writing,  and the writing or
writings are filed with the minutes of proceedings of the Board or committee.

          Section   15.   SHAREHOLDER   NOMINATION   OF   DIRECTOR   CANDIDATES.
NOTIFICATION  OF  NOMINATION.  Subject  to the rights of holders of any class or
series of stock having a preference  over another class or series of stock as to
dividends or upon  liquidation to elect  additional  directors  under  specified
circumstances,  nominations  for the  election of  directors  may be made by the
Board or a proxy committee appointed by the Board or by any shareholder entitled
to vote  in the  election  of  directors  generally.  However,  any  shareholder
entitled to vote in the election of directors generally may nominate one or more
persons for election as  directors  at a meeting only if written  notice of such
shareholder's  intent to make such  nomination  or  nominations  has been given,
either by personal  delivery or by United States mail,  postage prepaid,  to the
Secretary of the  Corporation  not later than (i) with respect to an election to
be held at an  annual  meeting  of  shareholders,  60  days in  advance  of such
meeting, and (ii) with respect to an election to be held at a special meeting of
shareholders for the election of directors, the close of business on the seventh
day  following  the date on  which  notice  of such  meeting  is first  given to
shareholders.  Each such notice shall set forth: (a) the name and address of the
shareholder  who intends to make the  nomination and the person or persons to be
nominated;  (b) a  representation  that the shareholder is a holder of record of
stock of the Corporation  entitled to vote at such meeting and intends to appear
in person or by proxy at the meeting to nominate the person or persons specified
in the notice;  (c) a description of all arrangements or understandings  between
the  shareholder  and each nominee and any other person or persons  (naming such
person or persons)  pursuant to which the  nomination or  nominations  are to be
made by the  shareholder;  (d) such other  information  regarding  each  nominee
proposed  by such  shareholder  as would be  required  to be included in a proxy
statement  filed  pursuant to the proxy  rules of the  Securities  and  Exchange

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Commission,  had the nominee been nominated, or intended to be nominated, by the
Board;  and (e) the  consent  of each  nominee  to  serve as a  director  of the
Corporation if so elected. The chairman of the meeting may refuse to acknowledge
the  nomination  of any  person  not  made  in  compliance  with  the  foregoing
procedure.

                                   ARTICLE III

                         EXECUTIVE AND OTHER COMMITTEES

         Section 1. EXECUTIVE AND OTHER COMMITTEES. The Board may, by resolution
passed by a majority of the whole Board, designate one or more committees,  each
committee  to consist of two or more of the  directors of the  Corporation.  The
Board may designate one or more directors as alternate members of any committee,
who may  replace  any  absent  or  disqualified  member  at any  meeting  of the
committee.  Any such committee,  to the extent provided in the resolution  shall
have and may exercise the powers of the Board in the  management of the business
and affairs of the Corporation, and may authorize the seal of the Corporation to
be affixed to all papers which may require it;  provided,  however,  that in the
absence or  disqualification  of any member of any such committee or committees,
the member or members thereof present at any meeting and not  disqualified  from
voting,  whether or not he or they constitute a quorum, may unanimously  appoint
another  member  of the  Board to act at the  meeting  in the  place of any such
absent  or  disqualified  member.  Each  committee  shall  keep  minutes  of its
proceedings  and shall report such minutes to the Board when required.  All such
proceedings  shall be subject to revision or alteration by the Board;  provided,
however,  that  third  parties  shall  not be  prejudiced  by such  revision  or
alteration.

         Section 2.  GENERAL.  A majority of any  committee  may  determine  its
action  and fix the time and  place of its  meetings,  unless  the  Board  shall
otherwise provide.  Notice of such meetings shall be given to each member of the
committee in the manner  provided for in Article II,  Section 7. The Board shall
have the power at any time to fill vacancies in, to change the membership of, or
to dissolve any such  committee.  Nothing  herein shall be deemed to prevent the
Board from appointing one or more  committees  consisting in whole or in part of
persons who are not directors of the  Corporation;  provided,  however,  that no
such committee shall have or may exercise any authority of the Board.

                                   ARTICLE IV

                                    OFFICERS

         Section 1. NUMBER AND  QUALIFICATIONS.  The officers of the Corporation
shall include the President,  one or more Vice  Presidents  (one or more of whom
may be  designated  Executive  Vice  President  or Senior Vice  President),  the
Treasurer, Controller, and the Secretary. Any two or more offices may be held by
the same person.  Such officers shall be elected from time to time by the Board,
each to hold  office  until the meeting of the Board  following  the next annual
meeting of the shareholders, or until his successor shall have been duly elected
and shall have  qualified,  or until his death, or until he shall have resigned,
or have been removed,  as hereinafter  provided in

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these By-Laws. The Board may from time to time elect a Chairman of the Board and
a Vice Chairman of the Board,  and the Board may from time to time elect, or the
Chairman  of the Board,  or the  President  may  appoint,  such  other  officers
(including one or more Assistant Vice  Presidents,  Assistant  Secretaries,  and
Assistant Treasurers), and such agents, as may be necessary or desirable for the
business of the  Corporation.  Such other  officers  and agents  shall have such
duties and shall hold their  offices for such terms as may be  prescribed by the
Board of by the appointing authority.

         Section 2.  RESIGNATIONS.  Any officer of the Corporation may resign at
any time by giving written notice of his resignation to the Board,  the Chairman
of the Board, the President or the Secretary.  Any such  resignation  shall take
effect at the time  specified  therein,  or,  if the time  when it shall  become
effective  shall not be specified  therein,  immediately  upon its receipt;  and
unless otherwise specified therein, the acceptance of such resignation shall not
be necessary to make it effective.

         Section 3.  REMOVAL.  Any  officer or agent of the  Corporation  may be
removed,  either with or without cause, at any time, by the vote of the majority
of the entire  Board at any meeting of the Board,  or,  except in the case of an
officer or agent elected or appointed by the Board, by the Chairman of the Board
or the  President.  Such removal shall be without  prejudice to the  contractual
rights, if any, of the person so removed.

         Section 4.  VACANCIES.  A vacancy in any office,  whether  arising from
death, resignation,  removal or any other cause, may be filled for the unexpired
portion  of the  term  of the  office  which  shall  be  vacant,  in the  manner
prescribed  in these  By-Laws for the regular  election or  appointment  to such
office. -

         Section 5.a. THE CHAIRMAN OF THE BOARD.  The Chairman of the Board,  if
one be elected,  shall be the chief  executive  officer of the  Corporation  and
shall have the general and active  management of the business of the Corporation
and general and active supervision and direction over the other officers, agents
and employees and shall see that their duties are properly performed.  He shall,
if present,  preside at each  meeting of the  shareholders  and of the Board and
shall be an ex officio member of all  committees of the Board.  He shall perform
all duties  incident to the office of Chairman of the Board and chief  executive
officer and such other duties as may from time to time be assigned to him by the
Board.

                  b. THE VICE  CHAIRMAN OF THE BOARD.  The Vice  Chairman of the
Board, if one be elected,  shall have such powers and perform all such duties as
from time to time may be  assigned  to him by the Board or the  Chairman  of the
Board and,  unless  otherwise  provided  by the Board,  shall in the case of the
absence or  inability  to act of the  Chairman of the Board,  shall  perform the
duties of the Chairman of the Board and when so acting shall have all the powers
of, and be subject to all the restrictions upon, the Chairman of the Board.

         Section 6. THE PRESIDENT.  The President  shall be the chief  operating
officer of the  Corporation  and shall have general and active  supervision  and
direction over the business and affairs of the  Corporation and over its several
officers,  subject,  however,  to the direction of the Chairman of the Board and
the control of the Board.  If no Chairman of the Board has been

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elected.  At the  request of the  Chairman  of the Board,  or in the case of his
absence or  inability  to act (unless  there be a Vice  Chairman of the Board so
designated to act),  the  President  shall perform the duties of the Chairman of
the Board and when so acting shall have all the powers of, and be subject to all
the  restrictions  upon, the Chairman of the Board.  He shall perform all duties
incident to the office of  President  and such other duties as from time to time
may be assigned to him by the Board, the Chairman of the Board or these By-Laws.

         Section 7. VICE-PRESIDENTS.  Each Executive Vice-President, each Senior
Vice-President  and each  Vice-President  shall have such powers and perform all
such  duties  as from  time to time may be  assigned  to him by the  Board,  the
Chairman of the Board or the President.

         Section 8. THE TREASURER.  The Treasurer  shall be the chief  financial
officer of the  Corporation  and shall  exercise  general  supervision  over the
receipt, custody and disbursement of Corporate funds. He shall have such further
powers  and  duties  as may be  conferred  upon  him  from  time  to time by the
President or the Board of  Directors.  He shall perform the duties of controller
if no one is elected to that office.

         Section 9. THE CONTROLLER. The Controller shall be the chief accounting
officer of the  Corporation and shall maintain  adequate  records of all assets,
liabilities and transactions of the Corporation; he shall establish and maintain
internal  accounting  control and, in cooperation  with the  independent  public
accountants  selected by the Board, shall supervise internal auditing.  He shall
have such further  powers and duties as may be  conferred  upon him from time to
time by the President or the Board of Directors.

         Section 10.  THE SECRETARY.  The Secretary shall

         (a)      keep or cause to be kept in one or more books provided for the
                  purpose,  the  minutes  of  all  meetings  of the  Board,  the
                  committees of the Board and the shareholders;

         (b)      see that all  notices  are duly given in  accordance  with the
                  provisions of these By-Laws and as required by law;

         (c)      be  custodian  of the records and the seal of the  Corporation
                  and affix and attest the seal to all stock certificates of the
                  Corporation  (unless  the  seal  of the  Corporation  on  such
                  certificates  shall be a facsimile,  as hereinafter  provided)
                  and affix and  attest  the seal to all other  documents  to be
                  executed on behalf of the Corporation under its seal;

         (d)      see that the  books,  reports,  statements,  certificates  and
                  other  documents  and  records  required by law to be kept and
                  filed are properly kept and filed; and

         (e)      in general,  perform all the duties  incident to the office of
                  Secretary  and such  other  duties as from time to time may be
                  assigned to him by the Board,  the  Chairman of the Board,  or
                  the President.

                                       9
<PAGE>

         Section  11.  OFFICERS'  BONDS OR OTHER  SECURITY.  If  required by the
Board,  any officer of the  Corporation  shall give a bond or other security for
the faithful  performance of his duties,  in such amount and with such surety or
sureties as the Board may require.

         Section  12.  COMPENSATION.  The  compensation  of the  officers of the
Corporation for their services as such officers shall be fixed from time to time
by the Board; provided,  however, that the Board may delegate to the Chairman of
the Board or the  President  the power to fix the  compensation  of officers and
agents appointed by the Chairman of the Board or the President,  as the case may
be.  An  officer  of the  Corporation  shall  not be  prevented  from  receiving
compensation  by  reason  of  the  fact  that  he is  also  a  director  of  the
Corporation,  but any such  officer who shall also be a director  shall not have
any vote in the determination of the amount of compensation paid to him.

                                    ARTICLE V

                                 INDEMNIFICATION

         Section 1.  INDEMNIFICATION-THIRD PARTY AND DERIVATIVE ACTIONS.

         (a) The  Corporation  shall indemnify any person made, or threatened to
be made, a party to an action or  proceeding  (other than one by or in the right
of the  Corporation  to  procure a  judgment  in its  favor),  whether  civil or
criminal, including an action by or in the right of any other corporation of any
type or kind,  domestic or foreign,  or any partnership,  joint venture,  trust,
employee benefit plan or other enterprise,  which any director or officer of the
Corporation served in any capacity at the request of the Corporation,  by reason
of the fact that he, his testator or intestate,  is or was a director or officer
of the Corporation, by reason of the fact that he, his corporation, partnership,
joint venture, trust, employee benefit plan or other enterprise in any capacity,
against  judgments,  fines,  amounts paid in settlement and expenses  (including
attorneys'  fees) incurred in connection with any such action or proceeding,  or
any appeal therein, provided that no indemnification may be made to or on behalf
of such person if (i) his acts were committed in bad faith or were the result of
his  active  and  deliberate  dishonesty  and were  material  to such  action or
proceeding  or (ii) he  personally  gained in fact a  financial  profit or other
advantage to which he was not legally entitled.

         (b) The  Corporation  shall indemnify any person made, or threatened to
be made, a party to an action by or in the right of the Corporation to procure a
judgment in its favor by reason of the fact that he, his testator or  intestate,
is or was a director or officer of the Corporation,  or is or was serving at the
request of the Corporation as a director or officer of any other  corporation of
any type or kind,  domestic or foreign,  or of any  partnership,  joint venture,
trust,  employee benefit plan or other  enterprise,  against  judgments,  fines,
amounts paid in settlement and expenses (including  attorneys' fees) incurred in
connection  with  such  action,   or  any  appeal  therein,   provided  that  no
indemnification  may be made to or on behalf of such person if (i) his acts were
committed  in bad  faith  or  were  the  result  of his  active  and  deliberate
dishonesty and were material to such action or (ii) he personally gained in fact
a financial profit or other advantage to which he was not legally entitled.

                                       10
<PAGE>

         (c) The  termination  of any civil or criminal  action or proceeding by
judgment,  settlement,  conviction  or upon a plea of  nolo  contendere,  or its
equivalent,  shall not in itself create a  presumption  that any such person has
not met the standard of conduct set forth in this Section 1.

         (d) For the  purpose of this  Section 1: (i) the  Corporation  shall be
deemed to have  requested a person to serve an employee  benefit  plan where the
performance by such person of his duties to the Corporation  also imposes duties
on, or otherwise involve services by, such person to the plan or participants or
beneficiaries  of the plan;  and (ii)  excise  taxes  assessed  on a person with
respect  to an  employee  benefit  plan  pursuant  to  applicable  law  shall be
considered fines.

         Section 2.  PAYMENT OF INDEMNIFICATION; REPAYMENT.

         (a) A person who has been  successful,  on the merits or otherwise,  in
the  defense  of a civil or  criminal  action  or  proceeding  of the  character
described in Section 1 of this Article V shall be entitled to indemnification as
authorized in such Section.

         (b)  Except  as  provided  in  paragraph  (a) of this  Section  2,  any
indemnification  under  Section 1 of this Article V, unless  ordered by a court,
shall be made by the Corporation only if authorized in the specific case:

                  (i) by the Board of Directors acting by a quorum consisting of
         directors who are not parties to the action or  proceeding  giving rise
         to the indemnity  claim upon a finding that the director or officer has
         met the  standard of conduct set forth in Section 1 of this  Article V;
         or (ii) if a quorum under the  foregoing  clause (i) is not  obtainable
         or, even if obtainable, a quorum of disinterested directors so directs:
         (A)  by  the  Board  of  Directors  upon  the  opinion  in  writing  of
         independent  legal  counsel  that  indemnification  is  proper  in  the
         circumstances because the standard of conduct set forth in Section 1 of
         this Article V has been met by such director or officer,  or (B) by the
         shareholders  of the  Corporation  upon a finding  that the director or
         officer has met such standard of conduct.

         (c) Expenses  Incurred by a director or officer in defending a civil or
criminal action or proceeding shall be paid by the Corporation in advance of the
final disposition of such action or proceeding upon receipt of an undertaking by
or on behalf of such  director  or  officer to repay  such  amount  incase he is
ultimately  found,  in  accordance  with this  Article V, not to be  entitled to
indemnification  or, where  indemnity is granted,  to the extent the expenses so
paid exceed the indemnification to which he is entitled.

         (d) Any  indemnification  of a director  or officer of the  Corporation
under Section 1 of this Article V, or advancement  of expenses  under  paragraph
(c) of this Section 2, shall be made promptly,  and in any event within 60 days,
upon the written request of the director of officer.

         Section  3.  ENFORCEMENT;  DEFENSES.  The right to  indemnification  or
advancement  of expenses  granted by this Article V shall be  enforceable by the
director or officer in any court of competent  jurisdiction  if the  Corporation
denies such request,  in whole or in part, or if no disposition  thereof is made
within 60 days after written  request by the director or officer.  Such person's
expenses  incurred in connection  with  successfully  establishing  his right to
indemnification,  in  whole  or in  part,  in any  such  action  shall  also  be
indemnified by the

                                       11
<PAGE>

Corporation.  It shall be a defense  to any such  action  (other  than an action
brought to enforce a claim for the  advancement  of expenses  under Section 2 of
this  Article  V  where  the  required  undertaking  has  been  received  by the
Corporation)  that the claimant has not met the standard of conduct set forth in
Section 1 of this Article V, but the burden of providing  such defense  shall be
on the Corporation.  Neither the failure of the Corporation (including its Board
of Directors,  its independent legal counsel, and its shareholders) to have made
a  determination  that   indemnification  of  the  claimant  is  proper  in  the
circumstances,  nor the fact that there has been an actual  determination by the
Corporation  (including its Board of Directors,  its independent  legal counsel,
and its shareholders) that  indemnification of the claimant is not proper in the
circumstances, shall be a defense to the action or create a presumption that the
claimant is not entitled to indemnification.

         Section 4.  SURVIVAL, SAVINGS CLAUSE; PRESERVATION OF OTHER RIGHTS.

         (a) The foregoing  indemnification  provisions  shall be deemed to be a
contract  between the  Corporation  and each  director and officer who serves in
such  capacity  at any time  while  these  provisions,  as well as the  relevant
provisions  of the New York  Business  Corporation  Law,  are in effect  and any
repeal or  modification  thereof shall not affect any right or  obligation  then
existing with respect to any state of facts then or  previously  existing or any
action or proceeding  previously or  thereafter  brought or threatened  based in
whole or in part upon any such state of facts.  Such a contract fight may not be
modified retroactively without the consent of such director or officer.

         (b) If this Article V or any portion hereof shall be invalidated on any
ground  by any  court of  competent  jurisdiction,  then the  Corporation  shall
nevertheless  indemnify  each  director  or officer of the  Corporation  against
judgments,  fines, amounts paid in settlement and expenses (including attorneys'
fees) incurred in connection with any actual or threatened action or proceeding,
whether civil or criminal,  including  any actual or threatened  action by or in
the  right  of the  Corporation,  or any  appeal  therein,  to the  full  extent
permitted by any  applicable  portion of this Article V that shall not have been
invalidated and to the full extent permitted by applicable law.

         (c) The indemnification  provided by this Article V shall not be deemed
exclusive of any other rights to which those  indemnified  may be entitled under
any by-law,  agreement,  vote of shareholders or directors or otherwise, both as
to action in his official  capacity and as to action in another  capacity  while
holding  such office,  and shall  continue as to a person who has ceased to be a
director or officer and shall inure to the benefit of the heirs,  executors  and
administrators of such a person. The Corporation is hereby authorized to provide
further  indemnification  if it deems advisable by resolution of shareholders or
directors, by amendment of these by-laws or by agreement.

         Section  5.  INSURANCE.  The  Corporation  may  purchase  and  maintain
insurance:

         (a) to indemnify the Corporation for any obligation  which it incurs as
a result of the  indemnification  of directors and officers under the provisions
of this Article V,

                                       12
<PAGE>

         (b) to indemnify  directors and officers in instances in which they may
be indemnified by the Corporation under the provisions of this Article V, and

         (c) to indemnify  directors and officers in instances in which they may
not otherwise be  indemnified  by the  Corporation  under the provisions of this
Article V, provided that the contract of insurance  covering such  directors and
officers pursuant to the foregoing  paragraph (c) of Section 4 of this Article V
shall provide,  in a manner acceptable to the  superintendent of insurance,  for
retention amount and for co-insurance,  and provided, further, that no insurance
under  this  Article  V may  provide  for any  payment,  other  than the cost of
defense, to or on behalf of any director or officer if a judgment or other final
adjudication adverse to the insured director or officer establishes (i) that his
acts of active and deliberate dishonesty were material to the cause of action so
adjudicated  or (ii) that the  director or officer  personally  gained in fact a
financial profit or other advantage to which he was not legally entitled.

         Section 6.  INDEMNIFICATION OF PERSONS NOT DIRECTORS OR OFFICERS OF THE
CORPORATION.  The  Corporation  may,  by  resolution  adopted  by the  Board  of
directors of the Corporation,  indemnify any person not a director or officer of
the Corporation,  who is made, or threatened to be made, a party to an action or
proceeding,  whether  civil or  criminal,  by reason  of the fact  that he,  his
testator or intestate,  is or was an employee or other agent of the Corporation,
against  judgments,  fines,  amounts paid in settlement and expenses  (including
attorneys'  fees) incurred in connection with such action or proceeding,  or any
appeal therein,  provided that no indemnification may be made to or on behalf of
such  person if (i) his acts were  committed  in bad faith or were the result of
active and deliberate dishonesty,  and such acts were material to such action or
proceeding,  or (ii) he  personally  gained in fact a financial  profit or other
advantage to which he was not legally entitled.

         Section 7.  RETROACTIVITY.  The right to  indemnification  conferred by
this Article V shall be retroactive to events  occurring prior to the adoption f
this Article V to the fullest extent permitted by law."

                                   ARTICLE VI

                 CONTRACTS, CHECKS, DRAFTS, BANK ACCOUNTS, ETC.

         Section 1.  EXECUTION OF  CONTRACTS.  Except as  otherwise  required by
statute,  the Certificate of  Incorporation  or these By-Laws,  any contracts or
other instruments may be executed and delivered in the name and on behalf of the
Corporation by such officer or officers (including any assistant officer) of the
Corporation  as the Board may from time to time direct.  Such  authority  may be
general or confined to specific  instances  as the Board may  determine.  Unless
authorized by the Board or expressly  permitted by these By-Laws,  an officer or
agent or employee shall not have any power or authority to bind the  Corporation
by  any  contract  or  engagement  or to  pledge  its  credit  or to  render  it
pecuniarily liable for any purpose or to any amount.

         Section 2. LOANS. Unless the Board shall otherwise determine either (a)
the  Chairman of the Board,  the  Vice-Chairman  of the Board or the  President,
singly, or (b) a Vice-President,  together with the Treasurer,  may effect loans
and advances at any time for the Corporation or

                                       13
<PAGE>

guarantee any loans and advances to any subsidiary of the Corporation,  from any
bank,  trust  company or other  institution,  or from any firm,  corporation  or
individual,  and for such  loans and  advances  may make,  execute  and  deliver
promissory  notes,  bonds or other  certificates or evidences of indebtedness of
the   Corporation,   or  guarantee  of   indebtedness  of  subsidiaries  of  the
Corporation,  but no officer or officers shall mortgage,  pledge, hypothecate or
transfer  any  securities  or other  property  of the  Corporation,  except when
authorized by the Board.

         Section 3. CHECKS,  DRAFTS, ETC. All checks,  drafts, bills of exchange
or other  orders for the  payment of money out of the funds of the  Corporation,
and all notes or other evidences of indebtedness  of the  Corporation,  shall be
signed in the name and on behalf of the  Corporation by such persons and in such
manner as shall from time to time be authorized by the Board.

         Section  4.  DEPOSITS.  All  funds  of the  Corporation  not  otherwise
employed shall be deposited  from time to time to the credit of the  Corporation
in such banks,  trust companies or other depositaries as the Board may from time
to time  designate  or as may be  designated  by any  officer or officers of the
Corporation to whom such power of designation may from time to time be delegated
by the Board.  For the purpose of deposit and for the purpose of collection  for
the account of the Corporation,  checks, drafts and other orders for the payment
of money  which are  payable to the order of the  Corporation  may be  endorsed,
assigned and  delivered by any officer or agent of the  Corporation,  or in such
other manner as the Board may determine by resolution.

         Section 5. GENERAL AND SPECIAL BANK  ACCOUNTS.  The Board may from time
to time  authorize  the opening and keeping of general and special bank accounts
with  such  banks,  trust  companies  or other  depositaries  as the  Board  may
designate or as may be designated by any officer or officers of the  Corporation
to whom such  power of  designation  may from time to time be  delegated  by the
Board.  The Board may make such special rules and regulations  with respect.  to
such bank accounts, not inconsistent with the provisions of these By-Laws, as it
may deem expedient.

         Section 6.  PROXIES IN RESPECT  OF  SECURITIES  OF OTHER  CORPORATIONS.
Unless otherwise provided by resolution  adopted by the Board of Directors,  the
Chairman of the Board, the President,  or a Vice-President may from time to time
appoint an attorney or attorneys or agent or agents, of the Corporation,  in the
name and on behalf of the  Corporation  to cast the votes which the  Corporation
may be entitled to cast as the holder of stock or other  securities in any other
corporation,  any  of  whose  stock  or  other  securities  may be  held  by the
Corporation, at meetings of the holders of the stock or other securities of such
other corporation,  or to consent in writing,  in the name of the Corporation as
such  holder,  to any action by such other  corporation,  and may  instruct  the
person or persons so  appointed as to the manner of casting such votes or giving
such consent,  and may execute or cause to be executed in the name and on behalf
of the Corporation and under its corporate seal, or otherwise,  all such written
proxies or other instruments as he may deem necessary or proper in the premises.

                                       14
<PAGE>

                                   ARTICLE VII

                                  SHARES, ETC.

         Section 1. STOCK  CERTIFICATES.  Each  holder of shares of stock of the
Corporation  shall be entitled to have a  certificate,  in such form as shall be
approved by the Board,  certifying the number of shares of the Corporation owned
by him.  The  certificates  representing  shares of stock shall be signed in the
name of the  Corporation  by the  Chairman  of the Board or the  President  or a
Vice-President  and by the Secretary or an Assistant  Secretary or the Treasurer
or an Assistant  Treasurer  and sealed with the seal of the  Corporation  (which
seal may be a facsimile, engraved or printed); provided, however, that where any
such certificate is countersigned by a transfer agent other than the Corporation
or its employee,  or is registered by a registrar  other than the Corporation or
one if its employees, the signature of the officers of the Corporation upon such
certificates  may be  facsimiles,  engraved or printed.  In case any officer who
shall  have  signed  or whose  facsimile  signature  has been  placed  upon such
certificates shall have ceased to be such officer before such certificates shall
be issued,  they may  nevertheless  be issued by the  Corporation  with the same
effect as if such officer were still in office at the date of their issue.

         Section 2. BOOKS OF ACCOUNT AND RECORD OF  SHAREHOLDERS.  The books and
records of the  Corporation  may be kept at such  places  within or without  the
State  of  incorporation  as the  Board  of  Directors  may  from  time  to time
determine. The stock record books and the blank stock certificate books shall be
kept by the Secretary or by any other  officer or agent  designated by the Board
of Directors.

         Section  3.  TRANSFER  OF SHARES.  Transfers  of shares of stock of the
Corporation  shall be made on the stock  records  of the  Corporation  only upon
authorization  by the registered  holder thereof,  or by his attorney  thereunto
authorized  by power of attorney  duly  executed and filed with the Secretary or
with a transfer clerk,  and on surrender of the certificate or certificates  for
such shares  properly  endorsed or accompanied by a duly executed stock transfer
power and the payment of all taxes thereon. Except as otherwise provided by law,
the  Corporation  shall be entitled to recognize the exclusive right of a person
in whose  name any share or shares  stand on the record of  shareholders  as the
owner of such share or shares for all purposes,  including,  without limitation,
the  rights to receive  dividends  or other  distributions,  and to vote as such
owner,  and the Corporation  may hold any such  shareholder of record liable for
calls and assessments  and the  Corporation  shall not be bound to recognize any
equitable or legal claim to or interesting  any such share or shares on the part
of any other person whether or not it shall have express or other notice thereof
Whenever any transfers of shares shall be made for  collateral  security and not
absolutely, and both the transferor and transferee request the Corporation to do
so, such fact shall be stated in the entry of the transfer.

         Section 4.  REGULATIONS.  The Board may make such additional  rules and
regulations,  not  inconsistent  with these  By-Laws,  as it may deem  expedient
concerning the issue,  transfer and  registration of certificates  for shares of
stock of the Corporation.  It may appoint,  or authorize any officer or officers
to appoint,  one or more transfer  agents or one or more transfer clerks and one
or more registrars and may require all  certificates for shares of stock to bear
the signature or signatures of any of them.

         Section 5. LOST, DESTROYED OR MUTILATED CERTIFICATES. The holder of any
certificate   representing  the  shares  of  stock  of  the  Corporation   shall
immediately  notify the  Corporation  of any loss,  destruction or mutilation of
such  certificate,  and the  Corporation may issue a new certificate of stock in
the place of any  certificate  theretofore  issued by it which the owner thereof

                                       15
<PAGE>

shall  allege to have been lost,  stolen,  or destroyed or which shall have been
mutilated, and the Board may, in its discretion, require such owner or his legal
representatives  to give to the  Corporation  a bond in  such  sum,  limited  or
unlimited, and in such form and with such surety or sureties as the Board in its
absolute  discretion shall determine,  to indemnify the Corporation  against any
claim that may be made  against it on account of the  alleged  loss,  theft,  or
destruction  of any such  certificate,  or the  issuance  of a new  certificate.
Anything  herein to the  contrary  notwithstanding,  the Board,  in its absolute
discretion,  may refuse to issue any such new  certificate,  except  pursuant to
legal proceedings under the laws of the State of incorporation.

         Section 6. FIXING OF RECORD  DATE.  In order that the  Corporation  may
determine the shareholders  entitled to notice of, or to vote at, any meeting of
shareholders  or any  adjournment  thereof,  or to express  consent to corporate
action in  writing  without a meeting,  or  entitled  to receive  payment of any
dividend  or other  distribution  or  allotment  of any  rights,  or entitled to
exercise any rights in respect of any change, conversion or exchange of stock or
for the purpose of any other  lawful  action,  the Board may fix, in advance,  a
record  date,  which  shall not be more than sixty nor less than ten days before
the date of such meeting,  nor more than sixty days prior to any other action. A
determination  of shareholders of record entitled to notice of, or to vote at, a
meeting of shareholders shall apply to any adjournment of the meeting; provided,
however, that the Board may fix a new record date for the adjourned meeting.

                                  ARTICLE VIII

                                     OFFICE

         Section 1. PRINCIPAL OR REGISTERED  OFFICE. The principal or registered
office of the  Corporation  shall be at such  place as may be  specified  in the
Certificate  of  Incorporation  of the  Corporation or other  certificate  filed
pursuant to law, or if none be so  specified,  at such place as may from time to
time be fixed by the Board.

         Section 2. OTHER OFFICES.  The  Corporation  also may have an office or
offices other than said principal or registered  office, at such place or places
either within or without the State of incorporation.

                                   ARTICLE IX

                                   FISCAL YEAR

         The fiscal year of the Corporation shall be determined by the Board.

                                       16
<PAGE>

                                    ARTICLE X

                                      SEAL

         The board shall  provide a corporate  seal which shall contain the name
of the  Corporation,  the  words  "Corporate  Seal"  and the year  and  State of
incorporation.

                                   ARTICLE XI

                                   AMENDMENTS

         These  By-Laws  may be  amended  or  repealed,  or new  By-Laws  may be
adopted, at any annual or special meeting of the shareholders,  by a majority of
the total votes of the shareholders or when shareholders are required to vote by
class by a majority of the appropriate  class,  present in person or represented
by proxy and entitled to vote on such action; provided, however, that the notice
of such meeting shall have been given as provided in these By-Laws, which notice
shall mention that amendment or repeal of these By-Laws,  or the adoption of new
By-Laws,  is one of the  purposes  of such  meeting.  These  By-Laws may also be
amended or repealed,  or new By-Laws may be adopted, by the Board at any meeting
thereof provided,  however, that notice of such meeting shall have been given as
provided in these  By-Laws,  which notice shall mention that amendment or repeal
of the By-Laws,  or the adoption of new By-Laws,  is one of the purposes of such
meetings;  and  provided,  further,  that  By-Laws  adopted  by the Board may be
amended or repealed by the shareholders as hereinabove provided.

                                       17EXHIBIT 4.6

                            [LOGO] ENZO BIOCHEM, INC.

              INCORPORATED UNDER THE LAWS OF THE STATE OF NEW YORK

                THIS CERTIFICATE IS TRANSFERABLE IN NEW YORK, NY

Number                                                                    Shares

                                                                 SEE REVERSE FOR
                                                             CERTAIN DEFINITIONS

                                                            CUSIP  294100  10  2

This certifies that

is the owner of

    FULL PAID AND NON-ASSESSABLE SHARES OF THE PAR VALUE OF ($.01) EACH OF THE
                       COMMON STOCK OF ENZO BIOCHEM, INC.

transferable only on the books of the Corporation by the holder hereof in person
or by duly authorized attorney upon surrender of this Certificate properly
endorsed.

         This Certificate and the shares represented hereby are issued and shall
be held subject to all of the provisions of the Certificate of Incorporation, as
amended, of the Corporation (a copy of which is on file at the office of the
Corporation) to all of which the holder of this certificate, by acceptance
hereof, assents. This certificate is not valid unless countersigned by the
Transfer Agent and Registrar.

         Witness the seal of the Corporation and the signatures of its duly
authorized officers.

Dated:

[Seal]                 Secretary                         President

Countersigned and Registered:
American Stock Transfer & Trust Company
(New York, NY)
            Transfer Agent and Registrar

            Authorized Signature

<PAGE>

         The following abbreviation, when used in the inscription on the face of
this certificate, shall be construed as though they were written out in full
according to applicable laws or regulations:

<TABLE>
<CAPTION>
<S>            <C>                              <C>              <C>
TEN COM     -  as tenants in common             UNIF GIFT MIN ACT____________Custodian_________
                                                                  (Cust)                (Minor)

TEN ENT     -  as tenants by the entireties                      under Uniform Gift to Minors

JT TEN      -  as joint tenants with right                       Act___________________________
               of survivorship and not as                                    (State)
               tenants in common
</TABLE>

     Additional abbreviations may also be used though not in the above list.

         For value received, ____________________ hereby sell, assign and
transfer unto

PLEASE INSERT SOCIAL SECURITY OR OTHER
    IDENTIFYING NUMBER OF ASSIGNEE

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

<TABLE>
<CAPTION>
<S>      <C>

....................................................................................................................
         (PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE)

....................................................................................................................

....................................................................................................................

shares of the capital stock represented by the within Certificate, and do hereby irrevocably constitute and appoint

....................................................................................................................
Attorney to transfer the said stock on the books of the within named Corporation with full power of substitution in
the premises.

Dated:..............................

NOTICE:  __________________________________________________________________________________________________________
         THE SIGNATURE TO THIS AGREEMENT MUST CORRESPOND WITH THE NAME AS WRITTEN UPON THE FACE OF THE CERTIFICATE
         IN EVERY PARTICULAR, WITHOUT ALTERATION OR ENLARGEMENT OR ANY CHANGE WHATEVER

Signature(s) Guaranteed:

-------------------------------------------------------------------------------------------------------------------
THE SIGNATURE(S) MUST BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION (BANKS, STOCKBROKERS, SAVINGS AND LOAN
ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM), PURSUANT TO
S.E.C. RULE 17Ad-15.
</TABLE>

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00081-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00081-of-00352.parquet"}]]