ARTICLES OF INCORPORATION

                                       OF

                         Quest Diagnostics Incorporated

                                    * * * * *


                  WE, THE UNDERSIGNED, Cynthia Montalvo, whose post-office
address is 1633 Broadway, New York, New York 10019, Gary Sherman, whose
post-office address is 1633 Broadway, New York, New York 10019 and Timothy E.
Carlson, whose post-office address is 1633 Broadway, New York, New York 10019 ,
each being at least eighteen years of age, do, under and by virtue of the
General Laws of the State of Maryland authorizing the formation of corporations,
associate dourselves as incorporators with the intention of forming a
corporation.


                  FIRST:  The name of the corporation is Quest Diagnostics 
Incorporated.

                  SECOND:  The purposes for which the corporation is formed are:

                  To engage in any or all lawful business for which corporations
may be organized under the Maryland General Corporation Law.

                  THIRD: The post-office address of the principal office of the
corporation in this State is c/o The Corporation Trust Incorporated, 32 South
Street, Baltimore, Maryland 21202. The name of the resident agent of the
corporation in this State is Corporation Trust Incorporated, a corporation of
this State, and the post-office address of the resident agent is 32 South
Street, Baltimore, Maryland 21202.

                  FOURTH: The total number of shares of stock which the
corporation shall have authority to issue is One Thousand (1,000) shares without
par value, all of one class.

                  FIFTH: The number of directors of the corporation shall be Two
(2), which may be changed in accordance with the by-laws of the corporation. The
names of the directors who shall act until the first annual meeting or until
their successors are duly chosen

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                                STATE OF MARYLAND

I hereby certify that this is a true and complete copy of the    3    page 
document on file in this office. DATED: 9-23-96 . 

                      STATE DEPARTMENT OF ASSESSMENTS AND TAXATION

BY:                                                                 , Custodian

This stamp replaces our previous certification system.  Effective:  6/95
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and qualify are:  Alister W. Reynolds and Douglas M. Van Oort.

                  IN WITNESS WHEREOF, the undersigned incorporators of Quest
Diagnostics Incorporated who executed the foregoing Articles of Incorporation
hereby acknowledge the same to be their act and further acknowledge that, to the
best of their knowledge the matters and facts set forth therein are true in all
material respects under the penalties of perjury.

                     Dated the 19th day of September, 1996.

                                            /s/ Cynthia Montalvo
                                            ----------------------------
                                            Cynthia Montalvo

                                            /s/ Gary Sherman
                                            ----------------------------
                                            Gary Sherman

                                            /s/ Timothy E. Carlson
                                            ----------------------------
                                            Timothy E. Carlson










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