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


                                    FORM S-8

             Registration Statement under the Securities Act of 1933


                           MOLECULAR BIOSYSTEMS, INC.
             (Exact name of Registrant as specified in its charter)

                                    Delaware
                                   36-3078632
                  (State or other jurisdiction (I.R.S. Employer
            of incorporation or organization) Identification Number)

                            10030 Barnes Canyon Road
                           San Diego, California 92121
                    (Address of principal executive offices)

                           Molecular Biosystems, Inc.
                             1998 Stock Option Plan
                            (Full title of the plan)

                                Bobba Venkatadri
                      President and Chief Executive Officer
                           Molecular Biosystems, Inc.
                            10030 Barnes Canyon Road
                           San Diego, California 92121
                                 (858) 812-7001
            (Name, address, including zip code, and telephone number,
                   including area code, of agent for service)



 ------------------------- ---------------------- ----------------------
   Title of Securities         Amount To Be          Proposed Maximum
    To Be Registered            Registered            Offering Price
                                                       Per Share(1)
-------------------------- ---------------------- ------------------------
-------------------------- ---------------------- ------------------------
  Common Stock, par          2,000,000 shares              $1.59
  value $.01 per share
-------------------------- ---------------------- ------------------------

-------------------------- ----------------------
    Proposed Maximum             Amount of
   Aggregate Offering          Registration
        Price(1)                  Fee(1)
-------------------------- ----------------------
-------------------------- ----------------------
      $3,180,000.00               $963.64

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

(1)  Computed pursuant to Rule 457(c), in accordance with Rule 457(h)(1), on the
     basis of the  average  of the high and low  sales  prices of a share of the
     Registrant's Common Stock reported on the New York Stock Exchange,  Inc. on
     September 30, 1999.




                                     PART I

              INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

Item 1.  Plan Information

         The  information  required by Item 1 is omitted from this  Registration
Statement in accordance with the Note to Part I of Form S-8.

Item 2.  Registrant Information and Employee Plan Annual Information

         The  information  required by Item 2 is omitted from this  Registration
Statement in accordance with the Note to Part I of Form S-8.


                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.  Incorporation of Documents by Reference

         The Registrant incorporates by reference in this Registration Statement
the following  documents  which the Registrant has filed with the Securities and
Exchange Commission (the "Commission"):

         (a) the Annual Report on Form 10-K which the  Registrant  filed for the
         fiscal year ended March 31, 1999;

         (b)    the Annual Report on Form 10K/A, dated March 31, 1999 and filed
on July 29, 1999;

         (c) the Quarterly  Report on Form 10-Q which the  Registrant  filed for
         the quarterly period ended June 30, 1999;

         (d) the Current Report on Form 8-K, dated May 3, 1999, and filed on May
13, 1999;

         (e) the description of the  Registrant's  Common Stock,  par value $.01
         per share,  contained in the  Registration  Statement on Form 8-A which
         the  Registrant  filed  on July 9,  1984  (Registration  No.  2-83721),
         together with any amendment or report that the  Registrant may file for
         the purpose of updating this description.

         All documents that the Registrant files with the Commission pursuant to
Sections 13(a),  13(c),  14 or 15(d) of the Securities  Exchange Act of 1934, as
amended, after the filing of this Registration Statement but prior to the filing
of a post-effective  amendment (1) which indicates that all of the shares of the
Registrant's Common Stock covered by this Registration  Statement (the "Shares")
have been sold or (2) which deregisters all of the Shares then remaining unsold,
shall  be  deemed  to be  incorporated  by  reference  in and to be part of this
Registration Statement from their respective dates of filing.

         Any statement in a document  incorporated  or deemed to be incorporated
by reference in this  Registration  Statement  shall be deemed to be modified or
superseded to the extent that a statement in this Registration  Statement, or in
any  document  filed after the filing of this  Registration  Statement  which is
deemed to be incorporated by reference in this Registration Statement,  modifies
or supersedes the earlier statement. The earlier statement shall be deemed to be
incorporated in this Registration Statement only as so modified or superseded.

Item 4.  Description of Securities

         This item is not applicable.

Item 5.  Interests of Named Experts and Counsel

         The legality of the Shares is being passed upon for the  Registrant  by
Johnson and Colmar, 300 South Wacker Drive, Suite 1000, Chicago, Illinois 60606,
who serve as the Registrant's outside general counsel.

         Craig P.  Colmar,  who is a partner of Johnson and Colmar,  is also the
Company's Assistant Secretary.  Mr. Colmar owns of record and beneficially 1,000
shares of Common Stock,  and other  partners of Johnson and Colmar own of record
and beneficially a further 1,000 shares.  In addition,  Mr. Colmar holds options
to purchase 57,250 shares of the Registrant's  Common Stock. These stock options
were granted at option prices equal to the fair market value of the Registrant's
Common Stock on the dates of grant.

Item 6.  Indemnification of Directors and Officers

         Section 145 of the Delaware General  Corporation Law provides generally
that a person sued as a director,  officer,  employee or agent of a  corporation
may be  indemnified  by the  corporation  in  non-derivative  suits for expenses
(including attorneys' fees), judgments,  fines and amounts paid in settlement if
he or she acted in good faith and in a manner that he or she reasonably believed
to be in, or not opposed to, the  corporation's  best interests.  In the case of
criminal actions and  proceedings,  the person must also not have had reasonable
cause to  believe  that his or her  conduct  was  unlawful.  Indemnification  of
expenses is also  authorized  in  stockholder  derivative  actions if the person
acted in good faith and in a manner that he or she reasonably believed to be in,
or not opposed to, the  corporation's  best  interests  and if he or she has not
been found liable to the corporation.  Even in this latter  instance,  the court
may determine that in view of all of the circumstances the person is entitled to
indemnification  for such expenses as the court deems proper. A person sued as a
director, officer, employee or agent of a corporation who has been successful in
defense of the action must be indemnified by the corporation  against his or her
expenses.

         Article  11  of  the  Registrant's  certificate  of  incorporation,  as
amended, requires the Registrant to indemnify its directors, officers, employees
and agents to the maximum  extent  permitted  by Delaware  law.  Article 11 also
requires  the  Registrant  to advance the  litigation  expenses of a director or
officer  upon  receipt of his or her  written  undertaking  to repay all amounts
advanced  if it is  ultimately  determined  that  he or she is not  entitled  to
indemnification.

         Section  102(b)(7) of the Delaware  General  Corporation  Law permits a
Delaware  corporation to include a provision in its certificate of incorporation
eliminating or limiting the personal  liability of a director to the corporation
or its  stockholders  for monetary  damages for breach of the director's duty of
care.  Such a provision  may not  eliminate or limit the liability of a director
for breaching his or her duty of loyalty, failing to act in good faith, engaging
in  intentional  misconduct or knowingly  violating a law,  declaring an illegal
dividend or  approving  an illegal  stock  repurchase,  or obtaining an improper
personal benefit.

         Article  10  of  the  Registrant's  certificate  of  incorporation,  as
amended,  eliminates the personal liability of the Registrant's directors to the
fullest extent permitted by Delaware law.

         Through  directors'  and  officers'   liability   insurance  which  the
Registrant maintains,  the Registrant's  directors and officers are also insured
against actual liabilities,  including  liabilities under the federal securities
laws, for acts or omissions related to the conduct of their duties.

Item 7.  Exemption from Registration Claimed

         This item is not applicable.

Item 8.  Exhibits

        4.1     Molecular Biosystems, Inc. 1998 Stock Option Plan

        5.1     Opinion of Johnson and Colmar

       23.1     Consent of Arthur Andersen LLP

       23.2     Consent of Johnson and Colmar (filed as part of Exhibit 5.1)

       24.1     Power of attorney (included under the caption "Power of Attorney
" on page 7).
Item 9.  Undertakings

Rule 415 Offering

         The Registrant undertakes:

                (1) to file,  during  any  period  in which  offers or sales are
         being made, a post-effective amendment to this Registration Statement:

                      (a) to include any prospectus required by Section 10(a)(3)
                of the  Securities  Act of 1933,  as  amended  (the  "Securities
                Act");

                      (b) to  reflect  in the  prospectus  any  facts or  events
                arising after the effective date of this Registration  Statement
                (or   the   most   recent   post-effective   amendment)   which,
                individually or in the aggregate, represent a fundamental change
                in the information set forth in this Registration Statement; and

                      (c) to include any  material  information  with respect to
                the  plan  of  distribution  not  previously  disclosed  in this
                Registration   Statement   or  any   material   change  to  such
                information in this Registration Statement;

         provided,  however, that undertakings (1)(a) and (1)(b) shall not apply
         if  the  information  required  to  be  included  in  a  post-effective
         amendment by those  undertakings is contained in periodic reports filed
         with or  furnished  to the  Commission  by the  Registrant  pursuant to
         Section 13 or Section 15(d) of the Securities  Exchange Act of 1934, as
         amended (the  "Exchange  Act") which are  incorporated  by reference in
         this Registration Statement;

                (2) that, for the purpose of determining any liability under the
         Securities Act, each such  post-effective  amendment shall be deemed to
         be a new  registration  statement  relating to the  securities  offered
         therein,  and the  offering  of such  securities  at that time shall be
         deemed to be the initial bona fide offering thereof; and

                (3) to remove  from  registration  by means of a  post-effective
         amendment any of the securities being registered which remain unsold at
         the termination of the offering; and

Filings Incorporating Subsequent Exchange Act Documents by Reference

         The  Registrant  undertakes  that,  for  purposes  of  determining  any
liability  under the  Securities  Act,  each filing of the  Registrant's  annual
report  pursuant to Section  13(a) or Section 15(d) of the Exchange Act which is
incorporated by reference in this Registration Statement shall be deemed to be a
new registration  statement relating to the securities offered therein,  and the
offering of such  securities at that time shall be deemed to be the initial bona
fide offering thereof.

Commission Position on Indemnification

         Insofar as indemnification for liabilities arising under the Securities
Act may be  permitted to  directors,  officers  and  controlling  persons of the
Registrant  pursuant to the Delaware General Corporation Law or the Registrant's
certificate of incorporation,  as amended,  as described in Item 6, or otherwise
permitted, the Registrant has been advised that in the opinion of the Commission
such indemnification is against public policy as expressed in the Securities Act
and is, therefore,  unenforceable. In the event that a claim for indemnification
against such  liabilities  (other than the payment by the Registrant of expenses
incurred or paid by a director,  officer or controlling person of the Registrant
in the successful defense of any action, suit or proceeding) is asserted by such
director,  officer or  controlling  person in  connection  with the Shares,  the
Registrant  will,  unless in the  opinion  of its  counsel  the  matter has been
settled by controlling precedent,  submit to a court of appropriate jurisdiction
the question  whether such  indemnification  by it is against  public  policy as
expressed in the Securities  Act and will be governed by the final  adjudication
of such issue.


                                   SIGNATURES

         Pursuant to the requirements of the Securities Act of 1933, as amended,
the Registrant certifies that it has reasonable grounds to believe that it meets
all of the  requirements  for  filing  on  Form  S-8 and has  duly  caused  this
Registration Statement to be signed on its behalf by the undersigned,  thereunto
duly authorized,  in the City of San Diego,  State of California,  on October 5,
1999.


                                       Molecular Biosystems, Inc.


                                       By:    /s/ ELIZABETH L. HOUGEN
                                              Elizabeth L. Hougen
                                              Executive Director of  Finance and
                                              Chief Financial Officer (Principal
                                              Financial and Accounting Officer)

<PAGE>

                                Power of Attorney

         Each person  whose  signature  appears  below who is then an officer or
director of the Registrant  authorizes Bobba Venkatadri and Elizabeth L. Hougen,
or either of them, with full power of substitution and  resubstitution,  to sign
in his name and to file any amendments (including  post-effective  amendments to
this Registration Statement) and all related documents necessary or advisable to
enable the Registrant to comply with the Securities Act of 1933, as amended,  in
connection  with the  registration  of the securities  which are covered by this
Registration  Statement,   which  amendments  may  make  such  changes  in  this
Registration  Statement  (as  it may  be so  amended)  as  Bobba  Venkatadri  or
Elizabeth  L. Hougen,  or either of them,  may deem  appropriate,  and to do and
perform all other related acts and things necessary to be done.

         Pursuant to the requirements of the Securities Act of 1933, as amended,
this  Registration  Statement has been signed below by the following  persons in
the capacities and on the dates indicated.



NAME                        TITLE                                DATE

/s/BOBBA VENKATARDI         President, Chief Executive Officer   October 5, 1999
   Bobba Venkatardi         and a Director (Principal
                            Executive Officer)


/s/ELIZABETH L. HOUGEN      Executive Director of Finance and    October 5, 1999
   Elizabeth L. Hougen      Chief Financial Officer(Principal
                            Financial and Accounting Officer)


/s/DAVID W. BARRY M.D.      Director                             October 5, 1999
   David W. Barry M.D.


/s/ROBERT W. BRIGHTFELT     Director                             October 5, 1999
   Robert W. Brightfelt

/s/CHARLES C. EDWARDS M.D.  Director                             October 5, 1999
   Charles C. Edwards M.D.

/s/JERRY T. JACKSON         Director                             October 5, 1999
   Jerry T. Jackson

/s/GORDON C. LUCE           Director                             October 5, 1999
   Gordon C. Luce

/s/DAVID RUBINFIEN          Director                             October 5, 1999
   David Rubinfien



                                Index to Exhibits

------------------------------- ------------------------------------------------
Exhibit Number      Description
-------------------------------------------------------------------------------

4.1                 Molecular Biosystems, Inc. 1998 Stock Option Plan

5.1                 Opinion of Johnson and Colmar

23.1                Consent of Arthur Andersen LLP

23.2                Consent of Johnson and Colmar (filed as part of Exhibit 5.1)

24.1                Power of Attorney (included under the caption "Power of
                    Attorney" on page 7).
[{"type": "S-8", "sequence": "1", "description": "1998 STOCK OPTION PLAN", "secsgml_size_bytes": 17717}]
{"company-data": {"conformed-name": "MOLECULAR BIOSYSTEMS INC", "cik": "0000719598", "assigned-sic": "2835", "irs-number": "363078632", "state-of-incorporation": "DE", "fiscal-year-end": "0331"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-88429", "film-number": "99722819"}, "business-address": {"street1": "10030 BARNES CANYON RD", "city": "SAN DIEGO", "state": "CA", "zip": "92121-2789", "phone": "6198127001"}, "mail-address": {"street1": "10030 BARNES CANYON ROAD", "city": "SAN DIEGO", "state": "CA", "zip": "92121"}}
UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM S-8

             Registration Statement under the Securities Act of 1933

                           MOLECULAR BIOSYSTEMS, INC.
             (Exact name of Registrant as specified in its charter)

                                    Delaware
                                   36-3078632
                  (State or other jurisdiction (I.R.S. Employer
            of incorporation or organization) Identification Number)

                            10030 Barnes Canyon Road
                           San Diego, California 92121
                    (Address of principal executive offices)

                           Molecular Biosystems, Inc.
                             1998 Stock Option Plan
                            (Full title of the plan)

                                Bobba Venkatadri
                      President and Chief Executive Officer
                           Molecular Biosystems, Inc.
                            10030 Barnes Canyon Road
                           San Diego, California 92121
                                 (858) 812-7001
            (Name, address, including zip code, and telephone number,
                   including area code, of agent for service)

 ------------------------- ---------------------- ----------------------
   Title of Securities         Amount To Be          Proposed Maximum
    To Be Registered            Registered            Offering Price
                                                       Per Share(1)
-------------------------- ---------------------- ------------------------
-------------------------- ---------------------- ------------------------
  Common Stock, par          2,000,000 shares              $1.59
  value $.01 per share
-------------------------- ---------------------- ------------------------

-------------------------- ----------------------
    Proposed Maximum             Amount of
   Aggregate Offering          Registration
        Price(1)                  Fee(1)
-------------------------- ----------------------
-------------------------- ----------------------
      $3,180,000.00               $963.64

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

(1)  Computed pursuant to Rule 457(c), in accordance with Rule 457(h)(1), on the
     basis of the  average  of the high and low  sales  prices of a share of the
     Registrant's Common Stock reported on the New York Stock Exchange,  Inc. on
     September 30, 1999.

                                     PART I

              INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

Item 1.  Plan Information

         The  information  required by Item 1 is omitted from this  Registration
Statement in accordance with the Note to Part I of Form S-8.

Item 2.  Registrant Information and Employee Plan Annual Information

         The  information  required by Item 2 is omitted from this  Registration
Statement in accordance with the Note to Part I of Form S-8.

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.  Incorporation of Documents by Reference

         The Registrant incorporates by reference in this Registration Statement
the following  documents  which the Registrant has filed with the Securities and
Exchange Commission (the "Commission"):

         (a) the Annual Report on Form 10-K which the  Registrant  filed for the
         fiscal year ended March 31, 1999;

         (b)    the Annual Report on Form 10K/A, dated March 31, 1999 and filed
on July 29, 1999;

         (c) the Quarterly  Report on Form 10-Q which the  Registrant  filed for
         the quarterly period ended June 30, 1999;

         (d) the Current Report on Form 8-K, dated May 3, 1999, and filed on May
13, 1999;

         (e) the description of the  Registrant's  Common Stock,  par value $.01
         per share,  contained in the  Registration  Statement on Form 8-A which
         the  Registrant  filed  on July 9,  1984  (Registration  No.  2-83721),
         together with any amendment or report that the  Registrant may file for
         the purpose of updating this description.

         All documents that the Registrant files with the Commission pursuant to
Sections 13(a),  13(c),  14 or 15(d) of the Securities  Exchange Act of 1934, as
amended, after the filing of this Registration Statement but prior to the filing
of a post-effective  amendment (1) which indicates that all of the shares of the
Registrant's Common Stock covered by this Registration  Statement (the "Shares")
have been sold or (2) which deregisters all of the Shares then remaining unsold,
shall  be  deemed  to be  incorporated  by  reference  in and to be part of this
Registration Statement from their respective dates of filing.

         Any statement in a document  incorporated  or deemed to be incorporated
by reference in this  Registration  Statement  shall be deemed to be modified or
superseded to the extent that a statement in this Registration  Statement, or in
any  document  filed after the filing of this  Registration  Statement  which is
deemed to be incorporated by reference in this Registration Statement,  modifies
or supersedes the earlier statement. The earlier statement shall be deemed to be
incorporated in this Registration Statement only as so modified or superseded.

Item 4.  Description of Securities

         This item is not applicable.

Item 5.  Interests of Named Experts and Counsel

         The legality of the Shares is being passed upon for the  Registrant  by
Johnson and Colmar, 300 South Wacker Drive, Suite 1000, Chicago, Illinois 60606,
who serve as the Registrant's outside general counsel.

         Craig P.  Colmar,  who is a partner of Johnson and Colmar,  is also the
Company's Assistant Secretary.  Mr. Colmar owns of record and beneficially 1,000
shares of Common Stock,  and other  partners of Johnson and Colmar own of record
and beneficially a further 1,000 shares.  In addition,  Mr. Colmar holds options
to purchase 57,250 shares of the Registrant's  Common Stock. These stock options
were granted at option prices equal to the fair market value of the Registrant's
Common Stock on the dates of grant.

Item 6.  Indemnification of Directors and Officers

         Section 145 of the Delaware General  Corporation Law provides generally
that a person sued as a director,  officer,  employee or agent of a  corporation
may be  indemnified  by the  corporation  in  non-derivative  suits for expenses
(including attorneys' fees), judgments,  fines and amounts paid in settlement if
he or she acted in good faith and in a manner that he or she reasonably believed
to be in, or not opposed to, the  corporation's  best interests.  In the case of
criminal actions and  proceedings,  the person must also not have had reasonable
cause to  believe  that his or her  conduct  was  unlawful.  Indemnification  of
expenses is also  authorized  in  stockholder  derivative  actions if the person
acted in good faith and in a manner that he or she reasonably believed to be in,
or not opposed to, the  corporation's  best  interests  and if he or she has not
been found liable to the corporation.  Even in this latter  instance,  the court
may determine that in view of all of the circumstances the person is entitled to
indemnification  for such expenses as the court deems proper. A person sued as a
director, officer, employee or agent of a corporation who has been successful in
defense of the action must be indemnified by the corporation  against his or her
expenses.

         Article  11  of  the  Registrant's  certificate  of  incorporation,  as
amended, requires the Registrant to indemnify its directors, officers, employees
and agents to the maximum  extent  permitted  by Delaware  law.  Article 11 also
requires  the  Registrant  to advance the  litigation  expenses of a director or
officer  upon  receipt of his or her  written  undertaking  to repay all amounts
advanced  if it is  ultimately  determined  that  he or she is not  entitled  to
indemnification.

         Section  102(b)(7) of the Delaware  General  Corporation  Law permits a
Delaware  corporation to include a provision in its certificate of incorporation
eliminating or limiting the personal  liability of a director to the corporation
or its  stockholders  for monetary  damages for breach of the director's duty of
care.  Such a provision  may not  eliminate or limit the liability of a director
for breaching his or her duty of loyalty, failing to act in good faith, engaging
in  intentional  misconduct or knowingly  violating a law,  declaring an illegal
dividend or  approving  an illegal  stock  repurchase,  or obtaining an improper
personal benefit.

         Article  10  of  the  Registrant's  certificate  of  incorporation,  as
amended,  eliminates the personal liability of the Registrant's directors to the
fullest extent permitted by Delaware law.

         Through  directors'  and  officers'   liability   insurance  which  the
Registrant maintains,  the Registrant's  directors and officers are also insured
against actual liabilities,  including  liabilities under the federal securities
laws, for acts or omissions related to the conduct of their duties.

Item 7.  Exemption from Registration Claimed

         This item is not applicable.

Item 8.  Exhibits

        4.1     Molecular Biosystems, Inc. 1998 Stock Option Plan

        5.1     Opinion of Johnson and Colmar

       23.1     Consent of Arthur Andersen LLP

       23.2     Consent of Johnson and Colmar (filed as part of Exhibit 5.1)

       24.1     Power of attorney (included under the caption "Power of Attorney
" on page 7).
Item 9.  Undertakings

Rule 415 Offering

         The Registrant undertakes:

                (1) to file,  during  any  period  in which  offers or sales are
         being made, a post-effective amendment to this Registration Statement:

                      (a) to include any prospectus required by Section 10(a)(3)
                of the  Securities  Act of 1933,  as  amended  (the  "Securities
                Act");

                      (b) to  reflect  in the  prospectus  any  facts or  events
                arising after the effective date of this Registration  Statement
                (or   the   most   recent   post-effective   amendment)   which,
                individually or in the aggregate, represent a fundamental change
                in the information set forth in this Registration Statement; and

                      (c) to include any  material  information  with respect to
                the  plan  of  distribution  not  previously  disclosed  in this
                Registration   Statement   or  any   material   change  to  such
                information in this Registration Statement;

         provided,  however, that undertakings (1)(a) and (1)(b) shall not apply
         if  the  information  required  to  be  included  in  a  post-effective
         amendment by those  undertakings is contained in periodic reports filed
         with or  furnished  to the  Commission  by the  Registrant  pursuant to
         Section 13 or Section 15(d) of the Securities  Exchange Act of 1934, as
         amended (the  "Exchange  Act") which are  incorporated  by reference in
         this Registration Statement;

                (2) that, for the purpose of determining any liability under the
         Securities Act, each such  post-effective  amendment shall be deemed to
         be a new  registration  statement  relating to the  securities  offered
         therein,  and the  offering  of such  securities  at that time shall be
         deemed to be the initial bona fide offering thereof; and

                (3) to remove  from  registration  by means of a  post-effective
         amendment any of the securities being registered which remain unsold at
         the termination of the offering; and

Filings Incorporating Subsequent Exchange Act Documents by Reference

         The  Registrant  undertakes  that,  for  purposes  of  determining  any
liability  under the  Securities  Act,  each filing of the  Registrant's  annual
report  pursuant to Section  13(a) or Section 15(d) of the Exchange Act which is
incorporated by reference in this Registration Statement shall be deemed to be a
new registration  statement relating to the securities offered therein,  and the
offering of such  securities at that time shall be deemed to be the initial bona
fide offering thereof.

Commission Position on Indemnification

         Insofar as indemnification for liabilities arising under the Securities
Act may be  permitted to  directors,  officers  and  controlling  persons of the
Registrant  pursuant to the Delaware General Corporation Law or the Registrant's
certificate of incorporation,  as amended,  as described in Item 6, or otherwise
permitted, the Registrant has been advised that in the opinion of the Commission
such indemnification is against public policy as expressed in the Securities Act
and is, therefore,  unenforceable. In the event that a claim for indemnification
against such  liabilities  (other than the payment by the Registrant of expenses
incurred or paid by a director,  officer or controlling person of the Registrant
in the successful defense of any action, suit or proceeding) is asserted by such
director,  officer or  controlling  person in  connection  with the Shares,  the
Registrant  will,  unless in the  opinion  of its  counsel  the  matter has been
settled by controlling precedent,  submit to a court of appropriate jurisdiction
the question  whether such  indemnification  by it is against  public  policy as
expressed in the Securities  Act and will be governed by the final  adjudication
of such issue.

                                   SIGNATURES

         Pursuant to the requirements of the Securities Act of 1933, as amended,
the Registrant certifies that it has reasonable grounds to believe that it meets
all of the  requirements  for  filing  on  Form  S-8 and has  duly  caused  this
Registration Statement to be signed on its behalf by the undersigned,  thereunto
duly authorized,  in the City of San Diego,  State of California,  on October 5,
1999.

                                       Molecular Biosystems, Inc.

                                       By:    /s/ ELIZABETH L. HOUGEN
                                              Elizabeth L. Hougen
                                              Executive Director of  Finance and
                                              Chief Financial Officer (Principal
                                              Financial and Accounting Officer)
Power of Attorney

         Each person  whose  signature  appears  below who is then an officer or
director of the Registrant  authorizes Bobba Venkatadri and Elizabeth L. Hougen,
or either of them, with full power of substitution and  resubstitution,  to sign
in his name and to file any amendments (including  post-effective  amendments to
this Registration Statement) and all related documents necessary or advisable to
enable the Registrant to comply with the Securities Act of 1933, as amended,  in
connection  with the  registration  of the securities  which are covered by this
Registration  Statement,   which  amendments  may  make  such  changes  in  this
Registration  Statement  (as  it may  be so  amended)  as  Bobba  Venkatadri  or
Elizabeth  L. Hougen,  or either of them,  may deem  appropriate,  and to do and
perform all other related acts and things necessary to be done.

         Pursuant to the requirements of the Securities Act of 1933, as amended,
this  Registration  Statement has been signed below by the following  persons in
the capacities and on the dates indicated.

NAME                        TITLE                                DATE

/s/BOBBA VENKATARDI         President, Chief Executive Officer   October 5, 1999
   Bobba Venkatardi         and a Director (Principal
                            Executive Officer)

/s/ELIZABETH L. HOUGEN      Executive Director of Finance and    October 5, 1999
   Elizabeth L. Hougen      Chief Financial Officer(Principal
                            Financial and Accounting Officer)

/s/DAVID W. BARRY M.D.      Director                             October 5, 1999
   David W. Barry M.D.

/s/ROBERT W. BRIGHTFELT     Director                             October 5, 1999
   Robert W. Brightfelt

/s/CHARLES C. EDWARDS M.D.  Director                             October 5, 1999
   Charles C. Edwards M.D.

/s/JERRY T. JACKSON         Director                             October 5, 1999
   Jerry T. Jackson

/s/GORDON C. LUCE           Director                             October 5, 1999
   Gordon C. Luce

/s/DAVID RUBINFIEN          Director                             October 5, 1999
   David Rubinfien

                                Index to Exhibits

------------------------------- ------------------------------------------------
Exhibit Number      Description
-------------------------------------------------------------------------------

4.1                 Molecular Biosystems, Inc. 1998 Stock Option Plan

5.1                 Opinion of Johnson and Colmar

23.1                Consent of Arthur Andersen LLP

23.2                Consent of Johnson and Colmar (filed as part of Exhibit 5.1)

24.1                Power of Attorney (included under the caption "Power of
                    Attorney" on page 7).