ADOPTED __/__/96


                              AMENDED AND RESTATED
                                   BY-LAWS OF
                               LIGHTBRIDGE, INC.


     Section 1.  CERTIFICATE OF INCORPORATION AND BY-LAWS

     1.1  These by-laws are subject to the certificate of incorporation of the
corporation.  In these by-laws, references to the certificate of incorporation
and by-laws mean the provisions of the certificate of incorporation and the by-
laws as are from time to time in effect.

     Section 2.  OFFICES

     2.1  Registered Office.  The registered office shall be in the City of
          -----------------                                                
Dover, County of Kent, State of Delaware.

     2.2  Other Offices.  The corporation may also have offices at such other
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places both within and without the State of Delaware as the board of directors
may from time to time determine or the business of the corporation may require.

     Section 3.  STOCKHOLDERS

     3.1  Location of Meetings.  All meetings of the stockholders shall be held
          --------------------                                                 
at such place either within or without the State of Delaware as shall be
designated from time to time by the board of directors.  Any adjourned session
of any meeting shall be held at the place designated in the vote of adjournment.

     3.2  Annual Meeting.  The annual meeting of stockholders shall be held at
          --------------                                                      
10:00 a.m. on the fourth [Wednesday] in [May] in each year (unless that day be a
legal holiday at the place where the meeting is to be held, in which case the
meeting shall be held at the same hour on the next succeeding day not a legal
holiday) (the "Specified Date"), or at such other date and time as shall be
designated from time to time by the board of directors, at which the
stockholders shall elect a board of directors and transact such other business
as may be required by law or these by-laws or as may properly come before the
meeting.

     3.3  Special Meeting in Place of Annual Meeting.  If the election for
          ------------------------------------------                      
directors shall not be held on the day designated by these by-laws, the
directors shall cause the election to be held as soon thereafter as convenient,
and to that end, if the annual meeting is omitted on the day herein provided
therefor or if the election of directors shall not be held thereat, a special
meeting of the stockholders may be held in place of such omitted meeting or
election, and any business transacted or election held at such special meeting
shall have the same effect as if transacted or held at the annual meeting, and
in such case all references in these by-laws to the annual meeting of the
stockholders, or to the annual election of directors, shall

 
be deemed to refer to or include such special meeting.  Any such special meeting
shall be called and the purposes thereof shall be specified in the call, as
provided in Section 3.4.

     3.4  Notice of Annual Meeting.  Written notice of the annual meeting
          ------------------------                                       
stating the place, date and hour of the meeting shall be given to each
stockholder entitled to vote at such meeting not less than ten nor more than
sixty days before the date of the meeting.  Such notice may specify the business
to be transacted and actions to be taken at such meeting.  No action shall be
taken at such meeting unless such notice is given, or unless waiver of such
notice is given by the holders of outstanding stock having not less than the
minimum number of votes necessary to take such action at a meeting at which all
shares entitled to vote thereon were voted.  Prompt notice of all action taken
in connection with such waiver of notice shall be given to all stockholders not
present or represented at such meeting.

     3.5  Other Special Meetings.  Special meetings of the stockholders, for any
          ----------------------                                                
purpose or purposes, unless otherwise prescribed by law or by the certificate of
incorporation, may be called by the president and shall be called by the
president or secretary at the request in writing of a majority of the board of
directors.  Such request shall state the purpose or purposes of the proposed
meeting and business to be transacted at any special meeting of the
stockholders.  Business transacted at any special meeting of stockholders shall
be limited to matters relating to the purpose or purposes stated in the notice
of meeting.

     3.6  Notice of Special Meeting.  Written notice of a special meeting
          -------------------------                                      
stating the place, date and hour of the meeting and the purpose or purposes for
which the meeting is called, shall be given not less than ten nor more than
sixty days before the date of the meeting, to each stockholder entitled to vote
at such meeting.  No action shall be taken at such meeting unless such notice is
given, or unless waiver of such notice is given by the holders of outstanding
stock having not less than the minimum number of votes necessary to take such
action at a meeting at which all shares entitled to vote thereon were voted.
Prompt notice of all action taken in connection with such waiver of notice shall
be given to all stockholders not present or represented at such meeting.

     3.7  Notice of Stockholder Business at Annual Meeting.  The following
          ------------------------------------------------                
provisions of this Section 3.7 shall apply to the conduct of business at any
annual meeting of the stockholders.  (As used in this Section 3.7, the term
annual meeting shall include a special meeting in lieu of an annual meeting.)

          (a) At any annual meeting of the stockholders, only such business
shall be conducted as shall have been brought before the meeting (i) pursuant to
the corporation's notice of meeting, (ii) by or at the direction of the board of
directors or (iii) by any stockholder of the corporation who is a stockholder of
record at the time of giving of the notice provided for in Section 3.7(b), who
is entitled to vote at such meeting and who has complied with the notice
procedures set forth in Section 3.7(b).

          (b) For business to be properly brought before any annual meeting of
the stockholders by a stockholder pursuant to clause (iii) of 3.7(a), the
stockholder must have given timely notice thereof in writing to the Secretary of
the corporation. To be timely, a stockholder's notice must be delivered to or
mailed and received at the principal executive


                                      -2-

 
offices of the corporation not less than sixty (60) days prior to the date for
such annual meeting, regardless of any postponements, deferrals or adjournments
of that meeting to a later date; provided, however, that if the annual meeting
of stockholders is to be held on a date prior to the Specified Date, and if less
than seventy (70) days' notice or prior public disclosure of the date of such
annual or special meeting is given or made, notice by the stockholder to be
timely must be so delivered or received not later than the close of business on
the tenth (10th) day following the earlier of the date on which notice of the
date of such meeting was mailed or the day on which public disclosure was made
of the date of such meeting.  A stockholder's notice to the Secretary shall set
forth as to each matter the stockholder proposes to bring before the annual
meeting (i) a brief description of the business desired to be brought before the
meeting and the reasons for conducting such business at the meeting, (ii) the
name and address, as they appear on the corporation's books, of the stockholder
proposing such business, the name and address of the beneficial owner, if any,
on whose behalf the proposal is made, and the name and address of any other
stockholders or beneficial owners known by such stockholder to be supporting
such proposal, (iii) the class and number of shares of the corporation which are
owned beneficially and of record by such stockholder of record, by the
beneficial owner, if any, on whose behalf the proposal is made and by any other
stockholders or beneficial owners known by such stockholder to be supporting
such proposal, and (iv) any material interest of such stockholder of record
and/or of the beneficial owner, if any, on whose behalf the proposal is made, in
such proposed business and any material interest of any other stockholders or
beneficial owners known by such stockholder to be supporting such proposal in
such proposed business, to the extent known by such stockholder.

     (c) Notwithstanding anything in these by-laws to the contrary, no business
shall be conducted at an annual meeting except in accordance with the procedures
set forth in this Section 3.7.  The person presiding at the annual meeting
shall, if the facts warrant, determine that business was not properly brought
before the meeting and in accordance with the procedures prescribed by these by-
laws, and if he should so determine, he shall so declare at the meeting and any
such business not properly brought before the meeting shall not be transacted.
Notwithstanding the foregoing provisions of this Section 3.7, a stockholder
shall also comply with all applicable requirements of the Securities Exchange
Act of 1934, as amended (or any successor provision), and the rules and
regulations thereunder with respect to the matters set forth in this Section
3.7.

     (d) This provision shall not prevent the consideration and approval or
disapproval at an annual meeting of reports of officers, directors and
committees of the board of directors, but, in connection with such reports, no
new business shall be acted upon at such meeting unless properly brought before
the meeting as herein provided.

     3.8  Stockholder List.  The officer who has charge of the stock ledger of
          ----------------                                                    
the corporation shall prepare and make, at least ten days before every meeting
of stockholders, a complete list of the stockholders entitled to vote at the
meeting, arranged in alphabetical order, and showing the address of each
stockholder and the number of shares registered in the name of each stockholder.
Such list shall be open to the examination of any stockholder, 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



                                      -3-

 
be held, which place shall be specified in the notice of the meeting, or, if not
so specified, at the place where the meeting is to be held.  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 stockholder who is present.

     3.9  Quorum of Stockholders.  The holders of a majority of the stock issued
          ----------------------                                                
and outstanding and entitled to vote thereat, present in person or represented
by proxy, shall constitute a quorum at all meetings of the stockholders for the
transaction of business except as otherwise required by law, or by the
certificate of incorporation or by these by-laws.  Except as otherwise provided
by law, no stockholder present at a meeting may withhold his shares from the
quorum count by declaring his shares absent from the meeting.

     3.10  Adjournment.  Any meeting of stockholders may be adjourned from time
           -----------                                                         
to time to any other time and to any other place at which a meeting of
stockholders may be held under these by-laws, which time and place shall be
announced at the meeting, by a majority of votes cast upon the question, whether
or not a quorum is present.  At such adjourned meeting at which a quorum shall
be present or represented any business may be transacted 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 the adjourned
meeting, a notice of the adjourned meeting shall be given to each stockholder of
record entitled to vote at the meeting.

     3.11  Proxy Representation.  Every stockholder may authorize another person
           --------------------                                                 
or persons to act for him by proxy in all matters in which a stockholder is
entitled to participate, whether by waiving notice of any meeting, objecting to
or voting or participating at a meeting, or expressing consent or dissent
without a meeting.  Every proxy must be signed by the stockholder or by his
attorney-in-fact.  No proxy shall be voted or acted upon after three years from
its date unless such proxy provides for a longer period.  Except as provided by
law, a revocable proxy shall be deemed revoked if the stockholder is present at
the meeting for which the proxy was given.  A duly executed proxy shall be
irrevocable if it states that it is irrevocable and, if, and only as long as, it
is coupled with an interest sufficient in law to support an irrevocable power.
A proxy may be made irrevocable regardless of whether the interest with which it
is coupled is an interest in the stock itself or an interest in the corporation
generally.  The authorization of a proxy may but need not be limited to
specified action, provided, however, that if a proxy limits its authorization to
a meeting or meetings of stockholders, unless otherwise specifically provided
such proxy shall entitle the holder thereof to vote at any adjourned session but
shall not be valid after the final adjournment thereof.

     3.12  Inspectors.  The directors or the person presiding at the meeting
           ----------                                                       
may, but need not, appoint one or more inspectors of election and any substitute
inspectors to act at the meeting or any adjournment thereof.  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, if any,
shall determine the number of shares of stock outstanding and the voting power
of each, the shares of stock represented at the meeting, the existence of a
quorum and the validity and effect of proxies, and shall receive votes, ballots
or consents, hear and determine all



                                      -4-

 
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 stockholders.
On request of the person presiding at the meeting, the inspectors shall make a
report in writing of any challenge, question or matter determined by them and
execute a certificate of any fact found by them.

     3.13  Action by Vote.  When a quorum is present at any meeting, whether the
           --------------                                                       
same be an original or an adjourned session, a plurality of the votes properly
cast for election to any office shall elect to such office and a majority of the
votes properly cast upon any question other than an election to an office shall
decide the question, except when a larger vote is required by law, by the
certificate of incorporation or by these by-laws.  No ballot shall be required
for any election unless requested by a stockholder present or represented at the
meeting and entitled to vote in the election.

     3.14  No Action by Consent.  Any action required or permitted to be taken
           --------------------                                               
by the stockholders of the corporation must be effected at a duly constituted
annual or special meeting of such stockholders and may not be effected by any
consent in writing by such stockholders.

     Section 4.  DIRECTORS

     4.1  Number.  The number of directors which shall constitute the whole
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board shall not be less than two nor more than nine, except that whenever there
shall be only one stockholder, such number shall be not less than one.  Within
the foregoing limits, the number of directors shall be determined by resolution
of the board of directors and may be increased or decreased at any time or from
time to time by the directors by vote of a majority of directors then in office,
except that any such decrease by vote of the directors shall only be made to
eliminate vacancies existing by reason of the death, resignation or removal of
one or more directors.  The directors shall be elected at the annual meeting of
the stockholders, except as provided in Section 4.7 of these by-laws.  Directors
need not be stockholders.

     4.2  Tenure.  Except as otherwise provided by law, by the certificate of
          ------                                                             
incorporation or by these by-laws, each director shall hold office until the
next annual meeting and until his successor is elected and qualified, or until
he sooner dies, resigns, is removed or becomes disqualified.

     4.3  Classes of Directors.  The board of directors shall be and is divided
          --------------------                                                 
into three classes:  Class I, Class II and Class III, each having as nearly as
possible the same number of directors.  If a fraction is contained in the
quotient arrived at by dividing the designated number of directors by three,
then, if such fraction is one-third, the extra director shall be a member of
Class III, and if such fraction is two-thirds, one of the extra directors shall
be a member of Class II and the other shall be a member of Class III, unless
otherwise provided from time to time by resolution adopted by the board of
directors.

     4.4  Terms of Office.  Each director shall serve for a term ending on the
          ---------------                                                     
date of the third annual meeting following the annual meeting at which such
director was elected;


                                      -5-

 
provided, that each initial director in Class I shall serve for a term ending on
the date of the annual meeting in 1997; each initial director in Class II shall
serve for a term ending on the date of the annual meeting in 1998; and each
initial director in Class III shall serve for a term ending on the date of the
annual meeting in 1999; and provided further, that the term of each director
shall be subject to the election and qualification of his successor and to his
earlier death, resignation or removal.

     4.5  Allocation of Directors Among Classes in the Event of Increases or
          ------------------------------------------------------------------
Decreases in the Number of Directors.  In the event of any increase or decrease
- ------------------------------------                                           
in the authorized number of directors, (a) each director then serving as such
shall nevertheless continue as a director of the class of which he is a member
and (b) the newly created or eliminated directorships resulting from such
increase or decrease shall be apportioned by the board of directors among the
three classes of directors so as to ensure that the classes have as nearly as
possible the same number of directors.  To the extent possible, consistent with
the foregoing rule, any newly created directorships shall be added to those
classes whose terms of office are to expire at the latest dates following such
allocation, and any newly eliminated directorships shall be subtracted from
those classes whose terms of offices are to expire at the earliest dates
following such allocation, unless otherwise provided from time to time by
resolution adopted by the board of directors.

     4.6  Powers.  The business of the corporation shall be managed by or under
          ------                                                               
the direction of the board of directors which shall have and may exercise all
the powers of the corporation and do all such lawful acts and things as are not
by law, the certificate of incorporation or these by-laws directed or required
to be exercised or done by the stockholders.

     4.7  Vacancies.  Any vacancy in the board of directors, however occurring,
          ---------                                                            
including a vacancy resulting from an enlargement of the board, shall be filled
by the vote of a majority of the directors then in office, although less than a
quorum, or by the sole remaining director.  When one or more directors shall
resign from the board, effective at a future date, a majority of the directors
then in office, including those who have resigned, shall have power to fill such
vacancy or vacancies, the vote or action by writing thereon to take effect when
such resignation or resignations shall become effective.  A director elected to
fill a vacancy shall hold office until the next election of the class for which
such director has been chosen, subject to the election and qualification of his
successor and to his earlier death, resignation or removal.  The directors shall
have and may exercise all their powers notwithstanding the existence of one or
more vacancies in their number, subject to any requirements of law or of the
certificate of incorporation or of these by-laws as to the number of directors
required for a quorum or for any vote or other actions.

     4.8  Nomination of Directors.  The following provisions of this Section 4.8
          -----------------------                                               
shall apply to the nomination of persons for election to the board of directors
at any annual meeting or special meeting of stockholders.

     (a) Nominations of persons for election to the board of directors of the
corporation at any annual meeting or special meeting of stockholders may be made
(i) by or at the direction of the board of directors or (ii) by any stockholder
of the corporation who is



                                      -6-

 
a stockholder of record at the time of giving of notice provided for in Section
4.8(b), who is entitled to vote for the election of directors at the meeting and
who has complied with the notice procedures set forth in Section 4.8(b).

     (b) Nominations by stockholders shall be made pursuant to timely notice in
writing to the Secretary of the corporation.  To be timely, a stockholder's
notice shall be delivered to or mailed and received at the principal executive
offices of the corporation, not less than sixty (60) days prior to the date for
the annual meeting, regardless of any postponements, deferrals or adjournments
of that meeting to a later date; provided, however, that if the annual meeting
of stockholders or a special meeting in lieu thereof is to be held on a date
prior to the Specified Date, and if less than seventy (70) days' notice or prior
public disclosure of the date of such annual or special meeting is given or
made, notice by the stockholder to be timely must be so delivered or received
not later than the close of business on the tenth (10th) day following the
earlier of the day on which notice of the date of such annual or special meeting
was mailed or the day on which public disclosure was made of the date of such
annual or special meeting.  Such stockholder's notice shall set forth (i) as to
each person whom the stockholder proposes to nominate for election or reelection
as a director all information relating to such person that is required to be
disclosed in solicitations of proxies for election of directors, or is otherwise
required, pursuant to Regulation 14A under the Securities Exchange Act of 1934,
as amended, or pursuant to any other then existing statute, rule or regulation
applicable thereto (including such person's written consent to being named in
the proxy statement as a nominee and to serving as a director if elected); (ii)
as to the stockholder giving the notice (A) the name and address, as they appear
on the corporation's books, of such stockholder and (B) the class and number of
shares of the corporation which are beneficially owned by such stockholder and
also which are owned of record by such stockholder; and (iii) as to the
beneficial owner, if any, on whose behalf the nomination is made, (A) the name
and address of such person and (B) the class and number of shares of the
corporation which are beneficially owned by such person.  The corporation may
require any proposed nominee to furnish such other information as may reasonably
be required by the corporation to determine the eligibility of such proposed
nominee as a director. At the request of the board of directors, any person
nominated by the board of directors for election as a director shall furnish to
the Secretary of the corporation that information required to be set forth in a
stockholder's notice of nomination which pertains to the nominee.

     (c) No person shall be eligible for election as a director of the
corporation at any annual meeting or special meeting of stockholders unless
nominated in accordance with the procedures set forth in this Section 4.8.  The
person presiding at the meeting shall, if the facts warrant, determine that a
nomination was not made in accordance with the procedures prescribed by these
by-laws, and if he should so determine, he shall so declare to the meeting and
the defective nomination shall be disregarded.  Notwithstanding the foregoing
provisions of this Section 4.8, a stockholder shall also comply with all
applicable requirements of the Securities Exchange Act of 1934, as amended (or
any successor provision), and the rules and regulations thereunder with respect
to the matters set forth in this by-law.



                                      -7-

 
     4.9  Committees.  The board of directors may, by vote of a majority of the
          ----------                                                           
whole board, (a) designate, change the membership of or terminate the existence
of any committee or committees, each committee to consist of one or more of the
directors; (b) designate one or more directors as alternate members of any such
committee who may replace any absent or disqualified member at any meeting of
the committee; and (c) determine the extent to which each such committee shall
have and may exercise the powers and authority of the board of directors in the
management of the business and affairs of the corporation, including the power
to authorize the seal of the corporation to be affixed to all papers which
require it and the power and authority to declare dividends or to authorize the
issuance of stock; excepting, however, such powers which by law, by the
certificate of incorporation or by these by-laws they are prohibited from so
delegating.  In the absence or disqualification of any member of such committee
and his alternate, if any, the member or members thereof present at any meeting
and not disqualified from voting, whether or not constituting a quorum, may
unanimously appoint another member of the board of directors to act at the
meeting in the place of any such absent or disqualified member.  Except as the
board of directors may otherwise determine, any committee may make rules for the
conduct of its business, but unless otherwise provided by the board or such
rules, its business shall be conducted as nearly as may be in the same manner as
is provided by these by-laws for the conduct of business by the board of
directors.  Each committee shall keep regular minutes of its meetings and report
the same to the board of directors upon request.

     4.10  Regular Meeting.  Regular meetings of the board of directors may be
           ---------------                                                    
held without call or notice at such place within or without the State of
Delaware and at such times as the board may from time to time determine,
provided that notice of the first regular meeting following any such
determination shall be given to absent directors.  A regular meeting of the
directors may be held without call or notice immediately after and at the same
place as the annual meeting of the stockholders.

     4.11  Special Meetings.  Special meetings of the board of directors may be
           ----------------                                                    
held at any time and at any place within or without the State of Delaware
designated in the notice of the meeting, when called by the president, or by
one-third or more in number of the directors, reasonable notice thereof being
given to each director by the secretary or by the president or by any one of the
directors calling the meeting.

     4.12  Notice.  It shall be reasonable and sufficient notice to a director
           ------                                                             
to send notice by mail at least forty-eight hours or by telegram at least
twenty-four hours before the meeting, addressed to him at his usual or last
known business or residence address or to give notice to him in person or by
telephone at least twenty-four hours before the meeting.  Notice of a meeting
need not be given to any director if a written waiver of notice, executed by him
before or after the meeting, is filed with the records of the meeting, or to any
director who attends the meeting without protesting prior thereto or at its
commencement the lack of notice to him.  Neither notice of a meeting nor a
waiver of a notice need specify the purposes of the meeting.

     4.13  Quorum.  Except as may be otherwise provided by law, by the
           ------                                                     
certificate of incorporation or by these by-laws, at any meeting of the
directors a majority of the directors then in office shall constitute a quorum.
In the event one or more of the directors shall be



                                      -8-

 
disqualified to vote at any meeting, then the required quorum shall be reduced
by one for each director so disqualified, provided that a quorum shall not in
any case be less than one-third of the total number of directors constituting
the whole board.  Any meeting may be adjourned from time to time by a majority
of the votes cast upon the question, whether or not a quorum is present, and the
meeting may be held as adjourned without further notice.

     4.14  Action by Vote.  Except as may be otherwise provided by law, by the
           --------------                                                     
certificate of incorporation or by these by-laws, when a quorum is present at
any meeting the vote of a majority of the directors present shall be the act of
the board of directors.

     4.15  Action Without a Meeting.  Unless otherwise restricted by the
           ------------------------                                     
certificate of incorporation or these by-laws, any action required or permitted
to be taken at any meeting of the board of directors or of any committee thereof
may be taken without a meeting if all the members of the board or of such
committee, as the case may be, consent thereto in writing, and such writing or
writings are filed with the records of the meetings of the board or of such
committee.  Such consent shall be treated for all purposes as the act of the
board or of such committee, as the case may be.

     4.16  Participation in Meetings by Conference Telephone.  Unless otherwise
           -------------------------------------------------                   
restricted by the certificate of incorporation or these by-laws, members of the
board of directors or of any committee thereof may participate in a meeting of
such board or committee by means of conference telephone or similar
communications equipment by means of which all persons participating in the
meeting can hear each other.  Such participation shall constitute presence in
person at such meeting.

     4.17  Compensation.  Unless otherwise restricted by the certificate of
           ------------                                                    
incorporation or these by-laws, the board of directors shall have the authority
to fix from time to time the compensation of directors.  The directors may be
paid their expenses, if any, of attendance at each meeting of the board of
directors and the performance of their responsibilities as directors and may be
paid a fixed sum for attendance at each meeting of the board of directors and/or
a stated salary as director.  No such payment shall preclude any director from
serving the corporation or its parent or subsidiary corporations in any other
capacity and receiving compensation therefor.  The board of directors may also
allow compensation for members of special or standing committees for service on
such committees.

     4.18  Interested Directors and Officers.
           --------------------------------- 

          (a) No contract or transaction between the corporation and one or more
of its directors or officers, or between the corporation and any other
corporation, partnership, association, or other organization in which one or
more of the corporation's directors or officers are directors or officers, or
have a financial interest, shall be void or voidable solely for this reason, or
solely because the director or officer is present at or participates in the
meeting of the board or committee thereof which authorizes the contract or
transaction, or solely because his or their votes are counted for such purpose,
if:

             (1) The material facts as to his relationship or interest and as to
the contract or transaction are disclosed or are known to the board of directors
or the committee,



                                      -9-

 
and the board or committee in good faith authorizes the contract or transaction
by the affirmative votes of a majority of the disinterested directors, even
though the disinterested directors be less than a quorum; or

           (2) The material facts as to his relationship or interest and as to
the contract or transaction are disclosed or are known to the stockholders
entitled to vote thereon, and the contract or transaction is specifically
approved in good faith by vote of the stockholders; or

           (3) The contract or transaction is fair as to the corporation as of
the time it is authorized, approved or ratified, by the board of directors, a
committee thereof, or the stockholders.

      (b)  Common or interested directors may be counted in determining the
presence of a quorum at a meeting of the board of directors or of a committee
which authorizes the contract or transaction.

     4.19  Resignation or Removal of Directors.  Directors of the corporation
           -----------------------------------                               
may be removed only for cause by the affirmative vote of the holders of at least
two-thirds of the shares of the capital stock of the corporation issued and
outstanding and entitled to vote at an election of directors.  Any director may
resign at any time by delivering his resignation in writing to the president or
the secretary or to a meeting of the board of directors.  Such resignation shall
be effective upon receipt unless specified to be effective at some other time;
and without in either case the necessity of its being accepted unless the
resignation shall so state.  No director resigning and (except where a right to
receive compensation shall be expressly provided in a duly authorized written
agreement with the corporation) no director removed shall have any right to
receive compensation as such director for any period following his resignation
or removal, or any right to damages on account of such removal, whether his
compensation be by the month or by the year or otherwise; unless in the case of
a resignation, the directors, or in the case of removal, the body acting on the
removal, shall in their or its discretion provide for compensation.

     Section 5.  NOTICES

     5.1  Form of Notice.  Whenever, under the provisions of law, or of the
          --------------                                                   
certificate of incorporation or of these by-laws, notice is required to be given
to any director or stockholder, such notice may be given by mail, addressed to
such director or stockholder, at his address as it appears on the records of the
corporation, with postage thereon prepaid, and such notice shall be deemed to be
given at the time when the same shall be deposited in the United States mail.
Unless written notice by mail is required by law, written notice may also be
given by telegram, cable, telecopy, commercial delivery service, telex or
similar means, addressed to such director or stockholder at his address as it
appears on the records of the corporation, in which case such notice shall be
deemed to be given when delivered into the control of the persons charged with
effecting such transmission, the transmission charge to be paid by the
corporation or the person sending such notice and not by the addressee.  Oral
notice or other in-hand delivery (in person or by telephone) shall be deemed
given at the time it is actually given.



                                     -10-

 
     5.2  Waiver of Notice.  Whenever notice is required to be given under the
          ----------------                                                    
provisions of law, the certificate of incorporation or these by-laws, a written
waiver thereof, signed by the person entitled to notice, whether before or after
the time stated therein, shall be deemed equivalent to notice.  Attendance of a
person at a meeting shall constitute a waiver of notice of such meeting, except
when the person attends a meeting for the express purpose of objecting, at the
beginning of the meeting, to the transaction of any business because the meeting
is not lawfully called or convened.  Neither the business to be transacted at,
nor the purpose of, any meeting of the stockholders, directors or members of a
committee of the directors need be specified in any written waiver of notice.

     Section 6.  OFFICERS AND AGENTS

     6.1  Enumeration; Qualification.  The officers of the corporation shall be
          --------------------------                                           
a president, a treasurer, a secretary and such other officers, if any, as the
board of directors from time to time may in its discretion elect or appoint
including without limitation one or more vice presidents.  Any officer may be,
but none need be, a director or stockholder.  Any two or more offices may be
held by the same person.  Any officer may be required by the board of directors
to secure the faithful performance of his duties to the corporation by giving
bond in such amount and with sureties or otherwise as the board of directors may
determine.

     6.2  Powers.  Subject to law, to the certificate of incorporation and to
          ------                                                             
the other provisions of these by-laws, each officer shall have, in addition to
the duties and powers herein set forth, such duties and powers as are commonly
incident to his office and such additional duties and powers as the board of
directors may from time to time designate.

     6.3  Election.  The board of directors at its first meeting after each
          --------                                                         
annual meeting of stockholders shall choose a president, a secretary and a
treasurer.  Other officers may be appointed by the board of directors at such
meeting, at any other meeting or by written consent.  At any time or from time
to time, the directors may delegate to any officer their power to elect or
appoint any other officer or any agents.

     6.4  Tenure.  Each officer shall hold office until the first meeting of the
          ------                                                                
board of directors following the next annual meeting of the stockholders and
until his successor is elected and qualified unless a shorter period shall have
been specified in terms of his election or appointment, or in each case until he
sooner dies, resigns, is removed or becomes disqualified.  Each agent of the
corporation shall retain his authority at the pleasure of the directors, or the
officer by whom he was appointed or by the officer who then holds agent
appointive power.

     6.5  President and Vice Presidents.  The president shall be the chief
          -----------------------------                                   
executive officer and shall have direct and active charge of all business
operations of the corporation and shall have general supervision of the entire
business of the corporation, subject to the control of the board of directors.
He shall preside at all meetings of the stockholders and of the board of
directors at which he is present, except as otherwise voted by the board of
directors.


                                     -11-

 
     The president or treasurer shall execute bonds, mortgages and other
contracts requiring a seal, under the seal of the corporation, except where
required or permitted by law to be otherwise signed and executed and except
where the signing and execution thereof shall be expressly delegated by the
board of directors to some other officer or agent of the corporation.

     Any vice presidents shall have such duties and powers as shall be
designated from time to time by the board of directors or by the president.

     6.6  Treasurer and Assistant Treasurers.  The treasurer shall be the chief
          ----------------------------------                                   
financial officer of the corporation and shall be in charge of its funds and
valuable papers, and shall have such other duties and powers as may be assigned
to him from time to time by the board of directors or by the president.

     Any assistant treasurers shall have such duties and powers as shall be
designated from time to time by the board of directors, the president or the
treasurer.

     6.7  Secretary and Assistant Secretaries.  The secretary shall record all
          -----------------------------------                                 
proceedings of the stockholders, of the board of directors and of committees of
the board of directors in a book or series of books to be kept therefor and
shall file therein all writings of, or related to, action by stockholder or
director consent.  In the absence of the secretary from any meeting, an
assistant secretary, or if there is none or he is absent, a temporary secretary
chosen at the meeting, shall record the proceedings thereof.  Unless a transfer
agent has been appointed, the secretary shall keep or cause to be kept the stock
and transfer records of the corporation, which shall contain the names and
record addresses of all stockholders and the number of shares registered in the
name of each stockholder.  The secretary shall have such other duties and powers
as may from time to time be designated by the board of directors or the
president.

     Any assistant secretaries shall have such duties and powers as shall be
designated from time to time by the board of directors, the president or the
secretary.

     6.8  Resignation and Removal.  Any officer may resign at any time by
          -----------------------                                        
delivering his resignation in writing to the president or the secretary or to a
meeting of the board of directors.  Such resignation shall be effective upon
receipt unless specified to be effective at some other time, and without in any
case the necessity of its being accepted unless the resignation shall so state.
The board of directors may at any time remove any officer either with or without
cause.  The board of directors may at any time terminate or modify the authority
of any agent.  No officer resigning and (except where a right to receive
compensation shall be expressly provided in a duly authorized written agreement
with the corporation) no officer removed shall have any right to any
compensation as such officer for any period following his resignation or
removal, or any right to damages on account of such removal, whether his
compensation be by the month or by the year or otherwise; unless in the case of
a resignation, the directors, or in the case of removal, the body acting on the
removal, shall in their or its discretion provide for compensation.


                                     -12-

 
     6.9  Vacancies.  If the office of the president or the treasurer or the
          ---------                                                         
secretary becomes vacant, the directors may elect a successor by vote of a
majority of the directors then in office.  If the office of any other officer
becomes vacant, any person or body empowered to elect or appoint that office may
choose a successor.  Each such successor shall hold office for the unexpired
term of his predecessor, and in the case of the president, the treasurer and the
secretary until his successor is chosen and qualified, or in each case until he
sooner dies, resigns, is removed or becomes disqualified.

     Section 7.  CAPITAL STOCK

     7.1  Stock Certificates.  Each stockholder shall be entitled to a
          ------------------                                          
certificate stating the number and the class and the designation of the series,
if any, of the shares held by him, in such form as shall, in conformity to law,
the certificate of incorporation and the by-laws, be prescribed from time to
time by the board of directors.  Such certificate shall be signed by the
president or a vice-president and (i) the treasurer or an assistant treasurer or
(ii) the secretary or an assistant secretary.  Any of or all the signatures on
the certificate may be a facsimile.  In case an officer, transfer agent or
registrar who has signed or whose facsimile signature has been placed on such
certificate shall have ceased to be such officer, transfer agent or registrar
before such certificate is issued, it may be issued by the corporation with the
same effect as if he were such officer, transfer agent, or registrar at the time
of its issue.

     7.2  Lost Certificates.  The board of directors may direct a new
          -----------------                                          
certificate or certificates to be issued in place of any certificate or
certificates theretofore issued by the corporation alleged to have been lost,
stolen or destroyed, upon the making of an affidavit of that fact by the person
claiming the certificate of stock to be lost, stolen or destroyed.  When
authorizing such issue of a new certificate or certificates, the board of
directors may, in its discretion and as a condition precedent to the issuance
thereof, require the owner of such lost, stolen or destroyed certificate or
certificates, or his legal representative, to advertise the same in such manner
as it shall require and/or to give the corporation a bond in such sum as it may
direct as indemnity against any claim that may be made against the corporation
with respect to the certificate alleged to have been lost, stolen or destroyed.

     Section 8.  TRANSFER OF SHARES OF STOCK

     8.1  Transfer on Books.  Subject to any restrictions with respect to the
          -----------------                                                  
transfer of shares of stock, shares of stock may be transferred on the books of
the corporation by the surrender to the corporation or its transfer agent of the
certificate therefor properly endorsed or accompanied by a written assignment
and power of attorney properly executed, with necessary transfer stamps affixed,
and with such proof of the authenticity of signature as the board of directors
or the transfer agent of the corporation may reasonably require.  Except as may
be otherwise required by law, by the certificate of incorporation or by these
by-laws, the corporation shall be entitled to treat the record holder of stock
as shown on its books as the owner of such stock for all purposes, including the
payment of dividends and the right to receive notice and to vote or to give any
consent with respect thereto and to be held liable for such calls and
assessments, if any, as may lawfully be made thereon, regardless of any
transfer, pledge or other disposition of such stock until the shares have been
properly transferred on the books of the corporation.



                                     -13-

 
     It shall be the duty of each stockholder to notify the corporation of his
post office address.

     Section 9.  GENERAL PROVISIONS

     9.1  Record Date.  In order that the corporation may determine the
          -----------                                                  
stockholders entitled to notice of or to vote at any meeting of stockholders 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 of directors may fix, in advance, a record date,
which shall not be more than sixty days nor less than ten days before the date
of such meeting, nor more than sixty days prior to any other action to which
such record date relates.  A determination of stockholders of record entitled to
notice of or to vote at a meeting of stockholders shall apply to any adjournment
of the meeting; provided, however, that the board of directors may fix a new
record date for the adjourned meeting.  If no record date is fixed,

          (a) The record date for determining stockholders entitled to notice of
or to vote at a meeting of stockholders shall be at the close of business on the
day next preceding the day on which notice is given, or, if notice is waived, at
the close of business on the day next preceding the day on which the meeting is
held;

          (b) The record date for determining stockholders entitled to express
consent to corporate action in writing without a meeting, when no prior action
by the board of directors is necessary, shall be the day on which the first
written consent is expressed; and

          (c) The record date for determining stockholders for any other purpose
shall be at the close of business on the day on which the board of directors
adopts the resolution relating to such purpose.

     9.2  Dividends.  Dividends upon the capital stock of the corporation may be
          ---------                                                             
declared by the board of directors at any regular or special meeting or by
written consent, pursuant to law.  Dividends may be paid in cash, in property,
or in shares of the capital stock, subject to the provisions of the certificate
of incorporation.

     9.3  Payment of Dividends.  Before payment of any dividend, there may be
          --------------------                                               
set aside out of any funds of the corporation available for dividends such sum
or sums as the directors from time to time, in their absolute discretion, think
proper as a reserve or reserves to meet contingencies, or for equalizing
dividends, or for repairing or maintaining any property of the corporation, or
for such other purpose as the directors shall think conducive to the interest of
the corporation, and the directors may modify or abolish any such reserve in the
manner in which it was created.

     9.4  Checks.  All checks or demands for money and notes of the corporation
          ------                                                               
shall be signed by such officer or officers or such other person or persons as
the board of directors may from time to time designate.



                                     -14-

 
     9.5  Fiscal Year.  The fiscal year of the corporation shall begin on the
          -----------                                                        
first day of January in each year and shall end on the last day of December next
following, unless otherwise determined by the board of directors.

     9.6  Seal.  The board of directors may, by resolution, adopt a corporate
          ----                                                               
seal.  The corporate seal shall have inscribed thereon the name of the
corporation, the year of its organization and the word "Delaware." The seal may
be used by causing it or a facsimile thereof to be impressed or affixed or
reproduced or otherwise.  The seal may be altered from time to time by the board
of directors.

     Section 10.  INDEMNIFICATION

     10.1  It being the intent of the corporation to provide maximum protection
available under the law to its officers and directors, the corporation shall
indemnify its officers and directors to the full extent the corporation is
permitted or required to do so by the General Corporation Law of Delaware.

     Section 11.  AMENDMENTS

     11.1  By the Board of Directors.  These by-laws may be altered, amended or
           -------------------------                                           
repealed or new by-laws may be adopted by the affirmative vote of a majority of
the directors present at any regular or special meeting of the board of
directors at which a quorum is present.

     11.2  By the Stockholders.  Notwithstanding any other provision of these
           -------------------                                               
by-laws, and notwithstanding the fact that a lesser percentage may be specified
by law, these by-laws may be altered, amended or repealed or new by-laws may be
adopted by the affirmative vote of the holders of at least seventy-five percent
(75%) of the shares of the capital stock of the corporation issued and
outstanding and entitled to vote at any regular or special meeting of
stockholders, provided notice of such alteration, amendment, repeal or adoption
of new by-laws shall have been stated in the notice of such regular or special
meeting.



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