UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 4
STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

[ ] Check this box if no longer subject to Section 16.
    Form 4 or Form 5 obligations may continue.
1. Name and Address of Reporting Person(s)
   Widder, Kenneth J
   10030 Barnes Canyon Blvd.
   
   
   San Diego, CA  92121
2. Issuer Name and Ticker or Trading Symbol
   Molecular Biosystems, Inc. (MB)
3. I.R.S. Identification Number of Reporting Person, if an entity (Voluntary)

4. Statement for Month/Year
   05/98
5. If Amendment, Date of Original (Month/Year)
6. Relationship of Reporting Person(s) to Issuer (Check all applicable)
   [X] Director                   [ ] 10% Owner 
   [X] Officer (give title below) [ ] Other (specify below)
   Chairman 
7. Individual or Joint/Group Filing (Check Applicable Line)
   [X] Form filed by One Reporting Person
   [ ] Form filed by More than One Reporting Person



Table I   Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
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1)Title of Security                           2)Trans-    3.Trans- 4.Securities Acquired(A)      5)Amount of    6)  7)Nature of     
                                              action      action   or Disposed of (D)            Securities         Indirect        
                                              Date        Code                   A               Beneficially   D   Beneficial      
                                              (Month/                            or              Owned at       or  Ownership       
                                              Day/Year)   Code V   Amount        D  Price        End of Month   I                   
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Common Stock                                  05/11/98    G        1,925         D  $10.3125     255,112        D  Direct           


Table II (PART 1)  Derivative Securities Acquired, Disposed of, or Beneficially Owned  (Columns 1 through 6)                        
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1)Title of Derivative          2)Conversion    3)Trans-       4)Trans-  5)Number of Derivative            6)Date Exercisable and    
Security                       or Exercise     action         action    Securities Acquired (A)           Expiration Date           
                               Price of        Date           Code      or Disposed of (D)                                          
                               Derivative                                                                                           
                               Security                       Code  V   A                D                Exercisable  Expiration   
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Table II (PART 2)  Derivative Securities Acquired, Disposed of, or Beneficially Owned  (Columns 1,3 and 7 through 11)               
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1)Title of Derivative          3)Trans-  7)Title and Amount                           8)Price     9)Number of   10) 11)Nature of    
Security                       action    of Underlying                                of Deri-    Derivative        Indirect        
                               Date      Securities                                   vative      Securities    D   Beneficial      
                                                                        Amount or     Security    Beneficially  or  Ownership       
                                                                        Number of                 Owned at      I                   
                  -                      Title                          Shares                    End of Month                      
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Explanation of Responses:




SIGNATURE OF REPORTING PERSON
/S/ By: Kevin S. Helmbacher
    For: Kenneth J Widder
DATE