Exhibit 3.1(b)













                           CERTIFICATE OF AMENDMENT
   
                                      OF THE
   
                          CERTIFICATE OF INCORPORATION

                                        OF
  
                             MALLINCKRODT GROUP INC.
    
                     ************************************

              UNDER SECTION 805 OF THE BUSINESS CORPORATION LAW

                     ************************************


<PAGE>    


 
                          CERTIFICATE OF AMENDMENT
 
                                   OF THE

                        CERTIFICATE OF INCORPORATION

                                     OF

                            MALLINCKRODT GROUP INC.

      ----------------------------------------------------------- 
           Under Section 805 of the Business Corporation Law

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

      

    Pursuant to Section 805 of the Business Corporation Law, the
undersigned, C. Ray Holman, Chairman of the Board and Chief Executive
Officer, and Roger A. Keller, Vice President and Secretary, hereby
certify as follows:

     I. The name of the Corporation is Mallinckrodt Group Inc.

    II. The Certificate of Incorporation of the Corporation (under
the name of International Agricultural Corporation) was originally
file by the Department of State, Albany, New York, on the 14th day of
June, 1909.

   III. The Certificate of Incorporation of the Corporation shall be
amended to change the name of the corporation, and to effect such
change, ARTICLE FIRST is hereby amended to read as follows:

        FIRST: The name of the Corporation is Mallinckrodt Inc.

    IV. This amendment to ARTICLE FIRST was authorized by the
unanimous affirmative vote of the Board of Directors of the
Corporation, followed by the affirmative vote of the holders of a
majority of the outstanding shares of the Corporation's 4% Cumulative
Preferred Stock and Common Stock voting as one class entitled to vote
thereon at the annual meeting of the stockholders of the Corporation
held on October 16, 1996.

    IN WITNESS WHEREOF, we have made and subscribed the Certificate
this 16th day of October, 1996, and the Chairman of the Board and
Chief Executive Officer of the Corporation has also verified this
Certificate.
  
                                 Mallinckrodt Group Inc.


                                 /s/ C. RAY HOLMAN                    

                                 ----------------------            
                                 C. Ray Holman, Chairman           
                                  of the Board and Chief Executive    
                                  Officer


                                 /s/ ROGER A. KELLER                  

                                 ----------------------- 
                                 Roger A. Keller, Vice President
                                  and Secretary

(Corporate Seal)


STATE OF MISSOURI    )
                     )
COUNTY OF ST. LOUIS  )

    C. Ray Holman, being duly sworn, deposes and says that he is
Chairman of the Board and Chief Executive Officer of Mallinckrodt
Group Inc., the corporation named and described in the foregoing
Certificate of Amendment; that he has read the foregoing Certificate
of Amendment and knows the contents thereof; and, that the same are
true of his own knowledge, except as to the matters therein stated to
be alleged upon information and belief, and as to those matters he
believes them to be true.


                                 /s/ C. RAY HOLMAN                    
  
                                 ------------------------- 
                                 C. Ray Holman, Chairman of the Board
                                  and Chief Executive Officer


Sworn to before me this
16th day of October, 1996


----------------------------
Notary Public

My commission expires: