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                                                                    EXHIBIT 3.81

                                     BYLAWS

                                       OF

                             DFW 5.01(a) CORPORATION

                         A TEXAS NON-PROFIT CORPORATION

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                                TABLE OF CONTENTS

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                                                                                                             Page
                                                                                                      

ARTICLE I -   PURPOSES, POWERS, AND DEFINITIONS...............................................................1
              Section 1.1 Statement of Purpose................................................................1
              Section 1.2 Powers .............................................................................1
              Section 1.3 Corporate Practice of Medicine .....................................................1


ARTICLE II -  OFFICES.........................................................................................2
              Section 2.1 Principal Place of Business.........................................................2
              Section 2.2 Registered Agent....................................................................2


ARTICLE III - MEMBERS.........................................................................................2
              Section 3.1 Qualifications, Powers, and Duties..................................................2
              Section 3.2 Annual Meeting......................................................................2
              Section 3.3 Special Meetings....................................................................2
              Section 3.4 Notice of Meetings, Waiver..........................................................2
              Section 3.5 Actions Reserved to the Member......................................................3
              Section 3.6 Action by Member(s)   ..............................................................4
              Section 3.7 Quorum..............................................................................4
              Section 3.8 Voting..............................................................................4
              Section 3.9 Membership Book.....................................................................4
              Section 3.10 No Cumulative Voting...............................................................4
              Section 3.11 Action Without A Meeting...........................................................4
              Section 3.12 Meetings by Telephone..............................................................5


ARTICLE IV -  DIRECTORS.......................................................................................5
              Section 4.1 General Powers......................................................................5
              Section 4.2 Actions Reserved to the Board.......................................................5
              Section 4.3 Qualifications and TSBME Requirements...............................................5
                      Section 4.3-1 Active Practice of Medicine...............................................5
                      Section 4.3-2 Conflicts of Interest.....................................................6
                      Section 4.3-3 Reporting Requirements....................................................6
                      Section 4.3-4 Financial Relationships...................................................6
              Section 4.4 Number..............................................................................6
              Section 4.5 Election of Directors...............................................................6
              Section 4.6 Term................................................................................7
              Section 4.7 Removal of Directors................................................................7
              Section 4.8 Vacancies...........................................................................7
              Section 4.9 Meetings............................................................................7
                      Section 4.9-1 Annual and Regular Meetings...............................................7
                      Section 4.9-2 Special Meetings..........................................................7
              Section 4.10 Waiver of Notice   ................................................................8
              Section 4.11 Quorum and Voting..................................................................8
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              Section 4.12 Proxies............................................................................8
              Section 4.13 Board Committees...................................................................8
                      Section 4.13-1 Quorum...................................................................8
                      Section 4.13-2 Membership...............................................................8
              Section 4.14 Action Without A Meeting...........................................................9
              Section 4.15 Resignation........................................................................9
              Section 4.16 Meetings by Telephone..............................................................9


ARTICLE V -   OFFICERS........................................................................................9
              Section 5.1 Number and Qualifications...........................................................9
              Section 5.2 Election and Term...................................................................9
              Section 5.3 Removal.............................................................................9
              Section 5.4 Vacancies...........................................................................9
              Section 5.5 Duties.............................................................................10
                      Section 5.5-1 President................................................................10
                      Section 5.5-2 Vice President...........................................................10
                      Section 5.5-3 Secretary................................................................10
                      Section 5.5-4 Treasurer................................................................10
                      Section 5.5-5 Assistant Officers.......................................................11
              Section 5.6 Insurance and Bonds of Officers   .................................................11
              Section 5.7 Delegation.........................................................................11
              Section 5.8 Resignations.......................................................................11

ARTICLE VI -  MISCELLANEOUS..................................................................................11
              Section 6.1 Contracts..........................................................................11
              Section 6.2 Checks, Drafts, Orders for Payment.................................................12
              Section 6.3 Depositories.......................................................................12
              Section 6.4 Voting of Shares and Membership Interests
                           Held by the Corporation...........................................................12
              Section 6.5 Books and Records..................................................................12
              Section 6.6 Fiscal Year; Accounting Election...................................................12
              Section 6.7 Loans Prohibited...................................................................12
              Section 6.8 Revocability of Authorizations.....................................................12
              Section 6.9 Transactions in Which Directors or Officers Are Interested 13
                      Section 6.9-1 Transactions.............................................................13
                      Section 6.9-2 Quorum...................................................................13
 ARTICLE VII- AMENDMENTS.....................................................................................13
              Section 7.1 Amendments.........................................................................13
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                                     BYLAWS

                                       OF


                             DFW 5.01(a) CORPORATION
                         A TEXAS NON-PROFIT CORPORATION


                                    ARTICLE 1
                        PURPOSES, POWERS, AND DEFINITIONS

     SECTION 1.1 STATEMENT OF PURPOSE. The purpose of the Corporation is to
further any or all purposes permitted under Section 5.01 of the Texas Medical
Practice Act, to function as provider organization with the goal of maintaining
health care services and developing new services and products to provide quality
services to the public in a cost-effective manner, and to transact any and all
other business permitted pursuant to the Texas Non-Profit Corporation Act.

     SECTION 1.2 POWERS. Except as limited by the Articles of Incorporation or
these Bylaws, the Corporation shall have and exercise such powers in furtherance
of its purposes as are now or may hereafter be granted by the laws of the State.

     SECTION 1.3 CORPORATE PRACTICE OF MEDICINE. Nothing herein shall be
construed as empowering the Member, any officer or employee of the Member, or
any non-physician whatsoever, with the authority to interfere with the
independent and professional practice of medicine by any director of the
Corporation or any physician employee of the Corporation or to intervene in or
interfere with the private doctor-patient relationship established between any
patient and any director of the Corporation or any physician employee of the
Corporation. All such physicians shall remain at all times free to exercise
their independent clinical judgments on behalf of their patients, subject only
to oversight by and the authority of physician supervisors.

     SECTION 1.4 DEFINITIONS. The terms set forth below shall have the following
meanings unless otherwise required by the context in which they may be used:

          ARTICLES OF INCORPORATION. The term "Articles of Incorporation" shall
     mean the Articles of Incorporation of the Corporation filed with the
     Secretary of State of the State of Texas on the 18th day of July, 1997, and
     any amendments thereto.

          BOARD. The term "Board" shall mean the Board of Directors of the
     Corporation.

          BYLAWS. The term "Bylaws" shall mean the Bylaws of the Corporation
     except where reference is specifically made to the bylaws of another entity
     or unit.

          CORPORATION. The term "Corporation" shall mean DFW 5.01(a)
     Corporation, a Texas non-profit corporation.

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          MEMBER. The term "Member" shall mean AmeriPath, Inc. or other members
     of the Corporation described in Section 3.1.

          STATE. The term "State" shall mean the State of Texas unless otherwise
     specifically indicated.

                                   ARTICLE II

                                     OFFICES

     SECTION 2.1 PRINCIPAL PLACE OF BUSINESS. The principal business office of
Corporation shall be located at 2330 Butler Street, Suite 115, Dallas, Texas
75235. The Corporation may also have offices at such other places both within
and without the State of Texas as the Board may from time to time determine or
the business of the Corporation may require.

     SECTION 2.2 REGISTERED AGENT. The Corporation shall have and continuously
maintain in the State of Texas a registered office and a registered agent whose
office is identical with such registered office. The registered office may be,
but need not be, identical with the principal business office of the Corporation
in the State of Texas, and the name of the registered agent and/or the address
of the registered office may be changed from time to time by the Board.

                                   ARTICLE III

                                     MEMBERS

     SECTION 3.1 QUALIFICATIONS, POWERS, AND DUTIES. The Corporation shall have
one Member which shall be AmeriPath, Inc. and/or other entities that meet such
standards as the initial Member shall establish. Such Member shall exercise such
rights and perform such duties as may be provided by law, the Corporation's
Articles of Incorporation, or these Bylaws.

     SECTION 3.2 ANNUAL MEETING. The Annual meeting of the Member shall be held
at the principal business office of the Corporation or at such other place
within or without the State of Texas as may be designated by the caller of the
meeting for approval of director nominees and the transaction of such other
business as may properly come before the meeting. The Annual meeting shall be
held on such date and at such time as shall be determined by the Board and
stated in the notice of meeting.

     SECTION 3.3 SPECIAL MEETINGS. Except as otherwise provided by law or by the
Articles of Incorporation, special meetings of the Member may be called by the
Member, the President or a majority of the Board, and shall be held at the
principal business office of the Corporation or such other location and at such
time as is stated in the notice calling such meeting.

     SECTION 3.4 NOTICE OF MEETINGS, WAIVER. So long as there is only one
Member, no notice shall be required of the annual meeting of the Member. If
there is more than one Member, written or printed notice stating the place, day
and hour of any meeting of the Members and, in case of a special meeting of the
Members, the purpose(s) for which the meeting is called, shall be delivered not
less than ten (10) nor more than sixty (60) days before the date of the meeting,

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either personally or by mail, to each Member of record entitled to vote at such
meeting. If mailed, such notice shall be deemed to be delivered when deposited
in the United States mail, postage prepaid, addressed to the Member at the
address as it appears on the records of the Corporation. Such further, earlier
or later notice shall be given as may be required by law. A Member waives notice
of a meeting by attendance at the meeting, unless such attendance is to object
to the transaction of any business on the ground that the meeting is not
lawfully called or convened, or by written waiver signed by the Member, whether
before or after the time stated therein. Such waiver shall be equivalent to the
giving of proper notice. No notice shall be necessary for any adjourned meeting.

     SECTION 3.5 ACTIONS RESERVED TO THE MEMBER. The Member shall exercise sole
authority in the removal of directors in accordance with Section 4.7 and the
appointment or removal of officers in accordance with Section 5.2. The following
matters shall require the approval of the Member of the Corporation following
consultation with the Board:

          (a)  The annual operating and capital budgets of the Corporation;

          (b)  Deviations in excess of $5,000.00 from annual operating and
               capital budgets;

          (c)  The sale, lease, mortgage, or other transfer or encumbrance of
               the real property of the Corporation;

          (d)  The sale, lease, mortgage, or other transfer or encumbrance of
               the personal property of the Corporation in excess of $5,000;

          (e)  The merger, acquisition, consolidation, liquidation, or
               dissolution of the Corporation;

          (f)  The borrowing or lending or money or the creation of indebtedness
               through the guaranty of another's debt or similar action;

          (g)  The working, giving or seeking of grants;

          (h)  The settlement of claims or litigation;

          (i)  Contracts or agreements in which the Corporation is at financial
               risk, including but not limited to employment contracts,
               management agreements and managed care contracts, including
               fee-for-service, discounted fee-for-service, risk pool, capitated
               and other "at risk" service agreements;

          (j)  Compensation and benefits for any physician employed or retained
               by the Corporation;

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          (k)  Subsequent to the organizing and incorporating physicians'
               selection of the initial Board, the appointment or election of
               directors in accordance with Section 4.5; and

          (l)  The altering, amending, or repeal of the Articles of
               Incorporation, or of these Bylaws in accordance with Section 7.1.

          (m)  Any power not specifically vested in the Board shall be reserved
               to the Member.

     SECTION 3.6 ACTION BY MEMBER(S). Any action which may be required by law,
the Articles of Incorporation, or these Bylaws to be taken by the Member shall
be evidenced in writing, signed by the president or any vice president of the
Member for and on behalf of the Member and shall be filed in the minute book of
the Corporation as part of the permanent records of the Corporation.

     SECTION 3.7 QUORUM. Except as otherwise provided by law, by the Articles of
Incorporation or by these Bylaws, a majority of the Members entitled to vote,
represented in person, shall constitute a quorum at a meeting of Members. If
less than a quorum of the Members is present at such meeting, a majority of the
Members present shall adjourn the meeting. The vote of a majority of the Members
entitled to vote and thus represented at a meeting at which a quorum is present
shall be the act of the Members, unless the vote of a greater number is required
by law or these Bylaws.

     SECTION 3.8 VOTING. At each Members meeting, every Member having the right
to vote shall be entitled to vote in person or by proxy. Each Member shall be
entitled to one vote on each matter submitted to a vote for which such Member is
entitled to vote. The act of a majority of the Members present and voting in
person or by proxy at any meeting at which there is a quorum shall be the act of
the Members.

     SECTION 3.9 MEMBERSHIP BOOK. The Corporation shall keep at its principal
business office, or the office of its transfer agent or registrar, a record of
its Members, giving the name and address of each Member.

     SECTION 3.10 NO CUMULATIVE VOTING. No Member may cumulate his votes at any
election of directors by giving one candidate as many votes as shall equal the
number of such directors multiplied by his vote, or by distributing such votes
on the same principle among any number of such candidates, or upon any other
matter.

     SECTION 3.11 ACTION WITHOUT A MEETING. Any action required or permitted to
be taken at a meeting of the Member may be taken without a meeting if a consent
in writing, setting forth the action to be taken, is signed and dated by the
Member.

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     SECTION 3.12 MEETINGS BY TELEPHONE. The Member may participate in and hold
a regular or special meeting by means of a conference telephone or any similar
communications equipment by means of which all persons participating in the
meeting may simultaneously hear each other.

     SECTION 3.13 NON-LIABILITY OF THE MEMBERS. The Member(s) of the Corporation
shall not be personally liable for the debts, liabilities, or obligations of the
Corporation.

                                   ARTICLE IV

                                    DIRECTORS

     SECTION 4.1 GENERAL POWERS. The business and affairs of the Corporation
shall be managed and controlled by the Board, and, subject to any restrictions
imposed by applicable law, by the Articles of Incorporation or by these Bylaws,
the Board may exercise all the powers of the Corporation.

     SECTION 4.2 ACTIONS RESERVED TO THE BOARD. To the extent specified below,
the following powers shall be exercised exclusively by the Board or, upon a
resolution approved by a majority of the Board, its physician designee(s):

                   SECTION 4.2-1 PRACTICE OF MEDICINE. These Bylaws shall be
          interpreted in a manner that reserves to physicians the sole authority
          to engage in the practice of medicine and reserves to the Corporation
          and its Board of Directors the sole authority to direct the medical,
          professional, and ethical aspects of the Corporation's practice of
          medicine.

                   SECTION 4.2-2 TERMINATION OF PHYSICIANS. The termination of
          the retention of any physician to provide medical services on behalf
          of the Corporation during such physician's term of retention may be
          accomplished only by the Board or its physician designee(s). Such
          termination shall be subject to due process procedures adopted by the
          Board or its physician designee(s) or provided by the retention
          agreement between the Corporation and the subject physician.

                   SECTION 4.2-3 PROFESSIONAL POLICIES APPROVAL. All
          credentialing, quality assurance, utilization review and peer review
          policies of the Corporation shall be approved exclusively by the
          Board.

     SECTION 4.3 QUALIFICATIONS AND TSBME REQUIREMENTS.

                   SECTION 4.3-1 ACTIVE PRACTICE OF MEDICINE. Each director
          shall (i) at all times be a physician duly licensed to practice
          medicine by the Texas State Board of Medical Examiners ("the TSBME")
          and actively engaged in the practice of medicine, and (ii) comply with
          the meeting attendance requirements established by the Board and set
          forth in the Corporation's policies and procedures. For purposes of
          these Bylaws, the term "actively engaged in the practice of medicine"
          shall be as defined by the TSBME.

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                  SECTION 4.3-2 CONFLICTS OF INTEREST. No director shall, at
          any time during his or her service on the Board, serve on the Board of
          Directors, be an officer, or serve in any capacity other than as a
          provider of professional services for or in any physician-hospital
          organization, physician organization, or other provider entity
          reasonably seen as being competitive with the Corporation.

                  SECTION 4.3-3 REPORTING REQUIREMENTS. At any time during his
         or her term of office, each director shall report to the TSBME any act
         or event which such director reasonably and in good faith believes
         constitutes a violation or attempted violation of the Medical Practice
         Act or the TSBME rules governing 5.01(a) organizations. Further, upon
         election or appointment and biennially thereafter as applicable, each
         director shall submit to the TSBME a sworn statement providing that (1)
         he or she is licensed by the TSBME; (2) he or she is actively engaged
         in the practice of medicine as defined by applicable regulations; (3)
         he or she shall exercise independent judgment as a director in all
         matters and, specifically in matters relating to credentialing, quality
         assurance, utilization review, peer review, and the practice of
         medicine; (4) in serving as a director of the Corporation, he or she
         shall use best efforts to cause the Corporation to comply with all
         relevant provisions of the Texas Medical Practice Act and TSBME rules;
         and (5) he or she shall report to the TSBME any action or event which
         such director reasonably and in good faith believes constitutes a
         violation or attempted violation of the Medical Practice Act or the
         TSBME rules governing 5.01(a) organizations.

                  SECTION 4.3-4 FINANCIAL RELATIONSHIPS. Any director or nominee
         who has a financial relationship with (i) any Member, (ii) any other
         director of the Corporation, (iii) any physician retained to provide
         medical services to or on behalf of the Corporation, (iv) any other
         person providing or anticipated to provide services or supplies to or
         on behalf of the Corporation in excess of $10,000 during a 12-month
         period, or (v) any affiliate of any of the parties identified in (i),
         (ii) or (iv), shall disclose the existence and nature of such
         relationship to the Member and the Board of Directors at the time of
         nomination, appointment and election, and also to the TSBME in the
         initial application and thereafter in any biennial statements.

     SECTION 4.4 NUMBER. The number of directors which shall constitute the
whole Board shall be not less than three (3). Except as to the number of initial
directors, the number of directors shall be determined by the Board and approval
of the Member of the Corporation.

     SECTION 4.5 ELECTION OF DIRECTORS. The initial directors shall be selected
by the organizing and incorporating physician(s) consistent with the
Corporation's missions, goals and purposes. Subsequent to the appointment of the
initial Directors, all successive Directors shall be selected in the following
manner: (1) The Member shall present a slate of nominees to the then current
Board; (2) The Board shall vote on the slate of candidates, and if the majority
of the Board approves the slate, the Member shall appoint one or more names on
the slate, as necessary, to fill the vacant positions; (3) If a majority of the
Board does not approve the slate of nominees, the Member shall propose a new
slate of nominees, and the procedure described in step two (2) shall be
repeated.
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     SECTION 4.6 TERM. The directors named in the Articles of Incorporation
shall hold office until their successors are elected and qualified. Thereafter,
directors shall be divided into two (2) classes for purposes of staggering terms
of office. Each group of directors shall be equal in number or as nearly equal
as possible to the number of directors in the other groups. The terms of office
of directors of the first group shall expire at the first annual meeting of
Member after their election, and the terms of the second group shall expire at
the second annual meeting after their election. At each annual meeting after
such classification, the number of directors equal to the number of the group
whose terms expires at the time of such annual meeting shall be elected to hold
office until the second succeeding annual meeting. No classification of
directors shall be effective prior to the first annual meeting of the Member.
Unless removed earlier, directors may serve unlimited two-year terms.

     SECTION 4.7 REMOVAL OF DIRECTORS. The following provisions govern the
removal of directors:

          (a)  BY THE MEMBER. The Member may remove a director without cause.

          (b)  BY THE CORPORATION.


               (i) Any director may be removed without cause by a majority vote
          of the Board of Directors, not including the director sought to be
          removed, provided that such removal is approved by the Member.

               (ii) Any director who ceases to meet the qualifications of this
          Article may be removed by the Board of Directors effective as of the
          date such qualifications cease to be met, and such removal shall not
          require the approval of the Member.

     SECTION 4.8 VACANCIES. Any vacancies among the directors shall be filled in
the manner specified in Section 4.5. A director elected to fill a vacancy shall
serve for the unexpired term of such director's predecessor in office.

     SECTION 4.9 MEETINGS.

                   SECTION 4.9-1 ANNUAL AND REGULAR MEETINGS. Regular meetings
         of the Board may be held with or without notice and at such time and at
         such place as shall be determined by the Board. The first meeting of
         each newly elected Board shall be held without notice immediately
         following the annual meeting of the Member and at the same place unless
         such time or place shall be changed by the unanimous consent of the
         directors then serving. Except as may be otherwise provided by law, by
         the Articles of Incorporation or by these Bylaws, neither the business
         to be transacted at nor the purpose of any regular meeting of the Board
         need be specified in the notice or waiver of notice of such meeting.

                    SECTION 4.9-2 SPECIAL MEETINGS. Special meetings of the
         Board may be called by the President or upon the written request of a
         majority of the directors. Notice of each special meeting of the Board
         shall be given to each director at least two (2) days before

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         the meeting, and such notice shall include the date, time, and place
         of the meeting. The purpose of the meeting need not be specified in the
         notice.

     SECTION 4.10 WAIVER OF NOTICE. Notice of a meeting of the Board need not be
given to any director who signs a waiver of notice either before or after the
meeting. Attendance of a director at any meeting shall constitute a waiver of
notice of such meeting, except when a director states, at the beginning of the
meeting or promptly upon arrival at the meeting, any objection to the
transaction of business because the meeting is not lawfully called or convened.
Except as otherwise provided by applicable law or by these Bylaws, neither the
business to be transacted at nor the purpose of any regular meeting or special
meeting of the Board need be specified in the waiver of notice of such meeting.

     SECTION 4.11 QUORUM AND VOTING. At all meetings of the Board, a majority of
the directors present in person shall constitute a quorum for the transaction of
business, and, unless otherwise specifically provided by law, the Articles of
Incorporation or these Bylaws, the act of a majority of the directors present
and voting in person at any meeting at which there is a quorum shall be the act
of the Board. If a quorum shall not be present at any meeting of directors, the
directors present shall adjourn the meeting without notice other than
announcement at the meeting.

     SECTION 4.12 PROXIES. Voting by proxies shall be prohibited.

     SECTION 4.13 BOARD COMMITTEES. The Board may by resolution adopted by a
majority of the directors designate and appoint committees, including but not
limited to an Executive Committee, which may or may not exercise the authority
of the Board, as determined by the Board. To the extent permitted by law, by
appropriate resolution the Board may authorize one or more committees to act on
its behalf when it is not in session. Neither the designation of one or more
committees to exercise authority of the Board nor the delegation to any
committee of such authority to a committee shall relieve the Board or any
individual director of any responsibility imposed upon the Board or such
director by law. Committee members shall be indemnified as are directors as
described in the Articles of Incorporation.

                   SECTION 4.13-1 QUORUM. A majority of the members of a Board
          committee shall constitute a quorum for the transaction of business at
          any meeting of the committee, unless otherwise specifically provided
          by the Articles of Incorporation or these Bylaws. If less than a
          majority of the members of the committee are present at such meeting,
          a majority of the committee members present may adjourn the meeting
          from time to time without further notice, until a quorum shall be
          present. A majority of all the members of any such committee may
          determine its action and fix the time and place of its meetings,
          unless the Board shall otherwise provide.

                   SECTION 4.13-2 MEMBERSHIP. Each committee shall consist of
          at least two persons. The Board shall have the power at any time to
          change the number of members of any such committee, or to fill
          vacancies, or to discharge any member or any such committee.
          Committee members may be appointed by the Board or, at the Board's
          option, by the individual designated by the Board to chair the
          committee. Unless otherwise provided by

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          the Board, committee members may be but need not be directors,
          except that any committee that exercises Board authority shall
          consist of a majority of directors. Any non-directors who is a
          committee member shall have the same responsibility with respect to
          the committee as shall a director who is a committee member.

     SECTION 4.14 ACTION WITHOUT A MEETING. Any action required or permitted to
be taken at a meeting of the Board or any Board committee may be taken without a
meeting if a consent in writing, describing the action so taken, is signed and
dated by all the members of the Board or committee, as the case may be.

     SECTION 4.15 RESIGNATION. A director may resign at any time by delivering
written notice to the Board or the president. A resignation is effective when
the notice is delivered unless the notice specifies a later effective date. If a
resignation is made effective at a later date, the pending vacancy may be filled
as outlined in Section 4.5 before the effective date provided that the successor
does not take office until the effective date.

     SECTION 4.16 MEETINGS BY TELEPHONE. Directors and committee members may
participate in and hold a regular or special meeting by means of a conference
telephone or any similar communications equipment by means of which all persons
participating in the meeting may simultaneously hear each other.

                                    ARTICLE V

                                    OFFICERS

     SECTION 5.1 NUMBER AND QUALIFICATIONS. The officers of the Corporation
shall consist of at least a president, one or more vice presidents, a secretary,
and a treasurer. The Corporation may also have such other officers and such
agents as the Member may from time to time determine. Any one person may serve
in more than one office, except that no one person shall simultaneously hold the
office of the president and the secretary: The officers need not be directors of
the Corporation.

     SECTION 5.2 ELECTION AND TERM. The Member shall select officers at its
first meeting at which a quorum shall be present after the annual meeting of
Member or whenever a vacancy exists. Each officer shall hold office for a
one-year term or until such officer's successor has been duly chosen and
qualified, or until his death, resignation or removal.

     SECTION 5.3 REMOVAL. Any officer or agent may be removed by the Member with
or without cause, but such removal shall be without prejudice to the contract
rights, if any, of the person so removed. Election or appointment of an officer
or agent shall not of itself create any contract rights.

     SECTION 5.4 VACANCIES. Any vacancy in any office for any cause may be
filled by the Member for the unexpired portion of the term.

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     SECTION 5.5 DUTIES. The officers of the Corporation shall have such powers
and duties, except as modified by the Member as applicable, as generally pertain
to their respective offices, as well as such powers and duties as from time to
time shall be conferred by the Board or Member as applicable and by these
Bylaws.

                   SECTION 5.5-1 PRESIDENT. The president shall serve as the
         chairman of the Board as well as the chief executive officer of the
         Corporation. The president shall have general direction of the affairs
         of the Corporation and general supervision over its several officers,
         subject to the control of the Board or Member as applicable. The
         president shall: (a) at each annual meeting, and from time to time,
         report to the Member and to the Board on all matters within the
         president's knowledge, which, in his opinion, the interest of the
         Corporation may require to be brought to their notice; (b) preside at
         all meetings of the Board; (c) attend all meetings of the Member; (d)
         sign and execute in the name of the Corporation all contracts or other
         instruments authorized by the Board, except in cases where the signing
         and execution thereof shall be expressly delegated or permitted by the
         Board, the Member or by these Bylaws to some other officer or agent of
         the Corporation; and (e) in general, perform all duties incident to the
         office of president, and such other duties as from time to time may be
         assigned by the Board or as are prescribed by these Bylaws.

                   SECTION 5.5-2 VICE PRESIDENT. Each vice president shall have
         such powers and duties as may be prescribed by the Board of Directors
         or as may be delegated from time to time by the president and (in the
         order as designated by the Board of Directors, or in the absence of
         such designation, as determined by the length of time each has held the
         office of vice president continuously) shall exercise the powers of the
         president during that officer's absence or inability to act. As between
         the Corporation and third parties, any action taken by a vice president
         in the performance of the duties of the president shall be conclusive
         evidence of the president's absence or inability to act at the time
         such action was taken.

                   SECTION 5.5-3 SECRETARY. The secretary shall: (a) prepare
         the minutes of all meetings of the Member and of the Board and keep
         such minutes, as well as the minutes of all committees of the Board, in
         one or more books provided for that purpose; (b) see that all notices
         are duly given in accordance with the provisions of these Bylaws or as
         required by law; (c) serve as custodian of the corporate records of the
         Corporation; (d) have general charge of such books and papers as the
         Board may direct, including, without limitation, a record of the names
         and addresses of all Members in alphabetical order, all of which shall,
         at all reasonable times, be open to the examination of any Member, or
         his agent or attorney, for any proper purpose; and (e) authenticate
         records of the Corporation. The secretary shall also perform all duties
         and exercise all powers incident to the office of the secretary and
         such other duties and powers as the Board and/or Member as applicable,
         or the president from time to time may assign or confer.

                   SECTION 5.5-4 TREASURER. The treasurer shall: (a) keep
         complete and accurate books and records of account, showing accurately
         at all times the financial condition of

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         the Corporation; (b) be the legal custodian of all monies, notes,
         securities, and other valuables that may from time to time come into
         the possession of the Corporation; and (c) furnish at meetings of the
         Board, or whenever requested, a statement of the financial condition of
         the Corporation. The treasurer shall also perform all duties and
         exercise all powers incident to the office of the treasurer and such
         other duties and powers as the Board and/or Member as applicable, or
         the president from time to time may assign or confer.

                   SECTION 5.5-5 ASSISTANT OFFICERS. Any assistant officer(s)
         appointed by the Board shall have power to perform, and shall perform,
         all duties incumbent upon the appropriate officer(s) of the Corporation
         subject to the general direction of such officers, and shall perform
         such other duties as the Bylaws may require or the Board or Member as
         applicable may prescribe.

     SECTION 5.6 INSURANCE AND BONDS OF OFFICERS. The Corporation shall
indemnify directors, officers, employees and agents of the Corporation to the
fullest extent required by the Texas Non-Profit Corporation Act as it may be
amended from time to time and shall indemnify such persons to the fullest extent
permitted by law. The Corporation shall also advance to such Indemnitee expenses
incurred in connection with any proceeding in which the indemnitee shall seek
indemnification to the fullest extent permitted by law. The Corporation may
secure insurance on behalf of directors and officers against any liability
asserted against them individually or collectively, for actions taken by them as
directors and officers. The Corporation may also procure a fidelity bond to
indemnify itself against the misfeasance or nonfeasance of any officer or
director. This provision shall be deemed to be a contract between the
Corporation and each indemnitee and shall not be amended without the written
agreement of the Corporation and the indemnitee affected by such amendment.

     SECTION 5.7 DELEGATION. The Board shall make appropriate delegations of
authority to the officers. In case of an officer's absence or for any other
reason, the Board or Member, as applicable, may delegate temporarily the powers
and duties of any officer of the Corporation to any other officer and may
authorize the delegation by any officer of the Corporation of any of his powers
and duties to any agent or employee subject to the general supervision by such
officer.

     SECTION 5.8 RESIGNATIONS. An officer may resign at any time by delivering
notice to the Board or Member as applicable. Any such resignation shall be made
in writing and shall take effect at the time it is delivered unless the notice
specifies a later effective date. The acceptance of a resignation shall not be
necessary to make it effective, unless expressly so provided in the resignation.
If a resignation is made effective at a later date and the Corporation accepts
such future effective date, the Board, subject to Member approval, may fill the
pending vacancy before the effective date provided that the successor does not
take office until the effective date.

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                                   ARTICLE VI
                                  MISCELLANEOUS

     SECTION 6.1 CONTRACTS. Subject to Member approval, the Board may authorize
any officer or officers, agent or agents, of the Corporation to enter into any
contract or execute and deliver any instrument in the name of and on behalf of
the Corporation, and such authority may be general or confined to specific
instances; and, unless so authorized by the Board or by these Bylaws, no
officer, agent or employee shall have any power or authority to bind the
Corporation by any contract or engagement, or to pledge its credit or to render
it liable pecuniarily for any purpose or any amount.

     SECTION 6.2 CHECKS, DRAFTS, ORDERS FOR PAYMENT. All checks, drafts, or
other orders for the payment of money and all notes or other evidences of
indebtedness issued in the name of the Corporation shall be signed by such
officer or officers of the Corporation and in such manner as shall from time to
time be determined by resolution of the Board subject to Member approval.

     SECTION 6.3 DEPOSITORIES. All funds of the Corporation shall be deposited
from time to time to the credit of the Corporation in one or more such banks,
trust companies or other depositories as the President may from time to lime
designate, upon such terms and conditions as shall be fixed by the President
subject to Member approval. The President may from time to time authorize the
opening and keeping with any such depository as it may designate, of general and
special bank accounts and may make such special rules and regulations with
respect thereto, not inconsistent with the provisions of these Bylaws, as it may
deem necessary.

     SECTION 6.4 VOTING OF SHARES AND MEMBERSHIP INTERESTS HELD BY THE
CORPORATION. Unless otherwise ordered by the Board, the president or, in the
president's absence or disability, the secretary, shall have full power and
authority on behalf of the Corporation to attend, to vote and to grant proxies
to be used at any meeting of members of such corporation in which the
Corporation may hold stock or voting membership. The Board, subject to approval
by the Member, may confer like powers upon any other person or persons.

     SECTION 6.5 BOOKS AND RECORDS. The Corporation shall keep correct and
complete books and records of account and shall also keep records of the actions
of the Corporation, which records shall be open to inspection by the Member at
any reasonable time.

     SECTION 6.6 FISCAL YEAR; ACCOUNTING ELECTION. The fiscal year of and the
method of accounting for the Corporation shall be as the Board shall determine
subject to Member approval.

     SECTION 6.7 LOANS PROHIBITED. No loans shall be made by the Corporation to
its directors, officers or employees, or to any other corporation, firm,
association, or other entity in which one or more of its directors, officers or
employees is a director, officer or employee or holds a substantial financial
interest.

     SECTION 6.8 REVOCABILITY OF AUTHORIZATIONS. No authorization, assignment,
referral or delegation of authority by the Board to any committee, officer,
agent or other official of the

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Corporation, or any other organization which is associated or affiliated with or
conducted under the auspices of the Corporation, shall preclude the Board from
exercising the authority required to meet its responsibility. The Board shall
retain the right to rescind any such Board authorization, assignment, referral
or delegation in its sole discretion.

     SECTION 6.9 TRANSACTIONS IN WHICH DIRECTORS OR OFFICERS ARE INTERESTED.

                   SECTION 6.9-1 TRANSACTIONS. No contract or other transaction
          between the Corporation and one or more of its directors or officers,
          or between the Corporation and any other corporation, firm, or entity
          in which one or more of the Corporation's directors or officers are
          directors or officers, or have a financial interest or whose immediate
          family members have a financial interest, shall be void or voidable
          solely because of such relationship or interest, or solely because
          such director(s) or officer(s) is (are) present at or participates in
          the meeting of the Board or a committee thereof that authorizes,
          approves, or ratifies such contract or transaction, or solely because
          his or their votes are counted for such purposes, if:

                         A. The fact of such relationship or interest is
                   disclosed or known to the Board or the committee that
                   authorizes, approves, or ratifies the contract or transaction
                   by a vote or consent sufficient for the purpose without
                   counting the votes or consents of such interested director(s)
                   or officer(s); or

                         B. The contract or transaction is fair and reasonable
                   as to the Corporation at the time it is authorized by the
                   Board or a committee thereof.

                   SECTION 6.9-2 QUORUM. Common or interested directors or
          officers may be counted in determining the presence of a quorum at a
          meeting of the Board or of a committee thereof that authorizes,
          approves, or ratifies such contract or transaction.

                                   ARTICLE VII
                                   AMENDMENTS

     SECTION 7.1 AMENDMENTS. Unless otherwise required by law, the Bylaws may be
altered, amended, or repealed, and new Bylaws adopted, by the Member subject to
the approval of a majority of the Board of Directors then in office.

Adopted as of the 21st day of July, 1997.

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