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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13D
Under the Securities Exchange Act of 1934
Amendment No.: 1
Name of Issuer: Molecular Dynamics, Inc.
Title of Class of Securities: Common Stock
CUSIP Number: 608514105
(Name, Address and Telephone Number of Person
Authorized To Receive Notices and Communications)
Mr. Arnold Snider c/o Deerfield Management,
450 Lexington Avenue, Suite 1930,
New York, New York 10017, (212) 551-1600
(Date of Event which Requires Filing of this Statement)
March 17, 1998
If the filing person has previously filed a statement on Schedule
13G to report the acquisition which is the subject of this
Schedule 13D, and is filing this schedule because of
Rule 13d-1(b)(3) or (4), check the following box [ ].
Note: Six copies of this statement, including all exhibits,
should be filed with the Commission. See Rule 13d-1(a) for other
parties to whom copies are to be sent.
*The remainder of this cover page shall be filled out for a
reporting person's initial filing on this form with respect to
the subject class of securities, and for any subsequent amendment
containing information which would alter the disclosures provided
in a prior cover page.
The information required in the remainder of this cover page
shall not be deemed to be "filed" for the purpose of Section 18
of the Securities Exchange Act of 1934 ("Act") or otherwise
subject to the liabilities of that section of the Act but shall
be subject to all other provisions of the Act (however, see the
Notes).
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CUSIP No. 608514105
1. Name of Reporting Person
S.S. or I.R.S. Identification No. of Above Person
Deerfield Capital, L.P.
2. Check the Appropriate Box if a Member of a Group
a.
b. x
3. SEC Use Only
4. Source of Funds
WC
5. Check if Disclosure of Legal Proceedings is Required Pursuant
to Items 2(d) or 2(e)
6. Citizenship or Place of Organization
Delaware
Number of Shares Beneficially Owned by Each Reporting Person
With:
7. Sole Voting Power:
8. Shared Voting Power:
834,670
9. Sole Dispositive Power:
10. Shared Dispositive Power:
834,670
11. Aggregate Amount Beneficially Owned by Each Reporting Person
834,670
12. Check Box if the Aggregate Amount in Row (11) Excludes
Certain Shares
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13. Percent of Class Represented by Amount in Row (11)
8.1%
14. Type of Reporting Person
PN
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CUSIP No. 608514105
1. Name of Reporting Person
S.S. or I.R.S. Identification No. of Above Person
Deerfield Management Company
2. Check the Appropriate Box if a Member of a Group
a.
b. x
3. SEC Use Only
4. Source of Funds
WC
5. Check if Disclosure of Legal Proceedings is Required Pursuant
to Items 2(d) or 2(e)
6. Citizenship or Place of Organization
New York
Number of Shares Beneficially Owned by Each Reporting Person
With:
7. Sole Voting Power:
8. Shared Voting Power:
115,330
9. Sole Dispositive Power:
10. Shared Dispositive Power:
115,330
11. Aggregate Amount Beneficially Owned by Each Reporting Person
115,330
12. Check Box if the Aggregate Amount in Row (11) Excludes
Certain Shares
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13. Percent of Class Represented by Amount in Row (11)
1.1%
14. Type of Reporting Person
PN
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CUSIP No. 608514105
1. Name of Reporting Person
S.S. or I.R.S. Identification No. of Above Person
Arnold H. Snider
2. Check the Appropriate Box if a Member of a Group
a.
b. x
3. SEC Use Only
4. Source of Funds
PF
5. Check if Disclosure of Legal Proceedings is Required Pursuant
to Items 2(d) or 2(e)
6. Citizenship or Place of Organization
United States
Number of Shares Beneficially Owned by Each Reporting Person
With:
7. Sole Voting Power:
10,000
8. Shared Voting Power:
950,000
9. Sole Dispositive Power:
10,000
10. Shared Dispositive Power:
950,000
11. Aggregate Amount Beneficially Owned by Each Reporting Person
960,000
12. Check Box if the Aggregate Amount in Row (11) Excludes
Certain Shares
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13. Percent of Class Represented by Amount in Row (11)
9.3%
14. Type of Reporting Person
IN
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The purpose of this Amendment No. 1 to the previously filed
Schedule 13D is to report a material change in the ownership of
Arnold Snider, Deerfield Capital, L.P. and Deerfield Management
Company in the Common Stock of Molecular Dynamics, Inc. (the
"Company"). All capitalized terms not defined herein have the
definitions given them in the original Schedule 13D.
Item 1. Security and Issuer
No change.
Item 2. Identity and Background
No change.
Item 3. Source and Amount of Funds or Other Consideration.
As of the date hereof, Mr. Snider is deemed to
beneficially own 960,000 shares of the Company's Common
Stock, Deerfield Capital is deemed to beneficially own
834,670 shares of the Company's Common Stock and
Deerfield Management is deemed to beneficially own
115,330 shares of the Company's Common Stock. 834,670
shares of Common Stock are held by Deerfield Partners,
L.P. and 115,330 shares are held by Deerfield
International Limited. 10,000 shares of Common Stock
are held by Mr. Snider personally. The shares of Common
Stock were purchased in open market transactions at an
aggregate cost of $8,484,360. The funds for the
purchase of the Common Stock held in the Funds came from
each entity's own funds or from margin loans entered
into in the ordinary course of business. The funds for
the purchase of the Common Stock held by Mr. Snider came
from his personal funds or from margin loans entered
into in the ordinary course of business.
Item 4. Purpose of Transactions.
No change.
Item 5. Interest in Securities of Issuer.
As of the date hereof, Mr. Snider is deemed to
beneficially own 960,000 shares of the Company's Common
Stock. Based on the Company's filing on Form 10-Q on
November 12, 1997, as of October 26, 1997 there were
10,351,426 shares of the Company's Common Stock
outstanding. Therefore, Mr. Snider is deemed to
beneficially own 9.3% of the Company's outstanding
shares of Common Stock. Deerfield Capital is deemed to
beneficially own 834,670 shares of Common Stock, equal
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to 8.1% of the Company's outstanding shares of Common
Stock. Deerfield Management is deemed to beneficially
own 115,330 shares of Common Stock, equal to 1.1% of the
Company's outstanding shares of Common Stock. Mr.
Snider personally beneficially owns 10,000 shares of
Common Stock, equal to .1% of the Company's outstanding
shares of Common Stock. Deerfield Capital and Deerfield
Management have the power to vote, direct the vote,
dispose of or direct the disposition of all the shares
of the Company's Common Stock that they each
respectively currently beneficially own. Mr. Snider has
shared power to vote, direct the vote, dispose of or
direct the disposition of all of the Company's Common
Stock that are beneficially owned by each of the other
Reporting Persons and sole power to vote, direct the
vote, dispose of and direct the disposition of all of
the Company's Common Stock personally beneficially owned
by him.
Item 6. Contracts, Arrangements, Understandings or
Relationships with Respect to Securities of the Issuer
No change.
Item 7. Material to be Filed as Exhibits.
1. An agreement relating to the filing of a joint
statement as required by Rule 13d-1(f) under the
Securities Exchange Act of 1934 is filed herewith
as Exhibit A.
2. A description of the transactions in the Shares
that were effected by the Reporting Persons since
60 days prior to March 17, 1998 through the date of
this filing is filed herewith as Exhibit B.
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Signature
The undersigned, after reasonable inquiry and to
the best of its knowledge and belief, certifies that the
information set forth in this statement is true, complete
and correct.
March 24, 1998
DEERFIELD CAPITAL, L.P.
By: Snider Capital Corp.,
General Partner
By: /s/ Arnold H. Snider
___________________________
Arnold H. Snider, President
DEERFIELD MANAGEMENT COMPANY
By: Snider Management Company,
General Partner
By: /s/ Arnold H. Snider
___________________________
Arnold H. Snider, President
ARNOLD H. SNIDER
/s/ Arnold H. Snider
___________________________
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Exhibit A
AGREEMENT
The undersigned agree that this Schedule 13D dated
March 24, 1998 relating to the Common Stock of Molecular
Dynamics, Inc. shall be filed on behalf of the undersigned.
DEERFIELD CAPITAL, L.P.
By: Snider Capital Corp.,
General Partner
By: /s/ Arnold H. Snider
___________________________
Arnold H. Snider, President
DEERFIELD MANAGEMENT COMPANY
By: Snider Management Company,
General Partner
By: /s/ Arnold H. Snider
___________________________
Arnold H. Snider, President
ARNOLD H. SNIDER
/s/ Arnold H. Snider
___________________________
00871001.AO9
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EXHIBIT B
SCHEDULE OF TRANSACTIONS
Transaction Shares Acquired Price Per Share
Date (Sold) (Not Including Commission)
______________ _______________ __________________________
3/17/98 55,000 $13.8977
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00871001.AO9
