FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person* ORBIMED ADVISORS LLC (Last) (First) (Middle) 767 THIRD AVENUE, 30TH FL (Street) NEW YORK NY 10017 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 04/05/2004	3. Issuer Name and Ticker or Trading Symbol MEMORY PHARMACEUTICALS CORP [ (MEMY) ]
		4. Relationship of Reporting Person(s) to Issuer (Check all applicable) X Director 10% Owner Officer (give title below) X Other (specify below) FN4	5. If Amendment, Date of Original Filed (Month/Day/Year)
			6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Series C preferred stock	(1)	(1)	Common Stock	711,706(2)	(1)	I	See 3 and 4(3)
Series D preferred stock	(1)	(1)	Common Stock	294,574(2)	(1)	I	See 3 and 4(4)

1. Name and Address of Reporting Person* ORBIMED ADVISORS LLC (Last) (First) (Middle) 767 THIRD AVENUE, 30TH FL (Street) NEW YORK NY 10017 (City) (State) (Zip)

1. Name and Address of Reporting Person* ISALY SAMUEL D (Last) (First) (Middle) 767 THIRD AVE (Street) NEW YORK NY 10017 (City) (State) (Zip)

1. Name and Address of Reporting Person* ORBIMED CAPITAL LLC (Last) (First) (Middle) 767 THIRD AVENUE (Street) NEW YORK NY 10017 (City) (State) (Zip)

1. Name and Address of Reporting Person* EATON VANCE WORLDWIDE HEALTH SCIENCES PORTFOLIO (Last) (First) (Middle) 767 THIRD AVENUE (Street) NEW YORK NY 10017 (City) (State) (Zip)

1. Name and Address of Reporting Person* PINSBURY WORLDWIDE PHARMACETICAL TRUST (Last) (First) (Middle) 767 THIRD AVENUE (Street) NEW YORK NY 10017 (City) (State) (Zip)

1. Name and Address of Reporting Person* PHARAMAW HEALTH (Last) (First) (Middle) 767 THIRD AVENUE (Street) NEW YORK NY 10017 (City) (State) (Zip)

Explanation of Responses:

1. Preferred Stock will automatically convert to common stock upon closing of the initial public offering of Memory Pharmaceuticals common stock (the "Closing"). Each share of Series C preferred stock ("C Stock") converts into 0.3559 shares of common stock and each share of Series D preferred stock ("D Stock") converts into 0.3333 shares of common stock.

2. Reporting Persons hold 2,883,722 preferred shares, which on the date of the Closing will be converted into 1,006,280 shares of common stock, on behalf of other persons who have the right to receive or the power to direct the receipt of dividends from, or proceeds from sale of, such securities. Of the 2,883,722 shares, both Eaton Vance Worldwide Health Sciences Portfolio ("Eaton") and Finsbury Worldwide Pharmaceutical Trust Plc ("Finsbury") is the direct holder of 400,000 shares of C Stock and 4 41,861 shares of D Stock. PharmaW/health ("Pharma") is the direct holder of 1,200,000 of C Stock. OrbiMed Advisors LLC ("Advisors"), pursuant to its authority under its investment advisory contracts with Eaton and Pharma, may be considered to hold indirectly 2,041,861 preferred shares and OrbiMed Capital LLC ("Capital"), pursuant to its authority of under its investment advisory contract Finsbury, may be considered to hold indirectly 841,861 preferred shares.

3. Advisors and Capital are registered advisers under the Investment Advisers Act of 1940, as amended, that act as investment advisers to certain collective investment funds which hold Shares of the Issuer. Samuel D. Isaly, a natural person, owns controlling interest in Advisors and Capital. Advisors acts as investment adviser to Eaton and Pharma. Capital acts as investment adviser to Finsbury. Pursuant to these agreements and relationships, Advisors and Capital have discretionary investment ma nagement authority with respect to the assets of Eaton, Pharma and Finsbury. Such authority includes the power to vote and otherwise dispose of securities purchased by the Eaton, Pharma and Finsbury. The reporting persons may be deemed to be a director of the issuer by virtue of their having nominated a representative to serve on the issuer's board of directors. Michael Sheffery currently serves as the reporting persons' representative on the issuer's board.

4. The Reporting Persons disclaim beneficial ownership of the these securities except to the extent of their pecuniary interest therein, and this report shall not be deemed an admission that the Reporting Person are the beneficial owners of such securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purposes.

	Samuel D. Isaly, Managing Member	04/06/2004
	** Signature of Reporting Person	Date
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