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

                                  SCHEDULE 13G
                    Under the Securities Exchange Act of 1934
                            (Amendment No. ________)*

                                (Name of Issuer)

                             LEXICON GENETICS, INC.

                         (Title of Class of Securities)

                                  COMMON STOCK

                                 (CUSIP Number)

                                    528872104

             (Date of Event which Requires Filing of this Statement)

                                DECEMBER 31, 2000

Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

        |_|   Rule 13d-1(b)
        |_|   Rule 13d-1(c)
        |X|   Rule 13d-1(d)

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

* 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 on 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).

CUSIP No. 528872104                    13G                     Page 2 of 7 Pages
- --------------------------------------------------------------------------------
1   NAME OF REPORTING PERSON
    S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

    PATRICOF & CO. VENTURES, INC.    13-2647531
- --------------------------------------------------------------------------------
2   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
                                                                         (a) |_|
                                                                         (b) |_|
- --------------------------------------------------------------------------------
3   SEC USE ONLY

- --------------------------------------------------------------------------------
4   CITIZENSHIP OR PLACE OF ORGANIZATION

    New York
- --------------------------------------------------------------------------------
                  5    SOLE VOTING POWER

                       -0-
                  --------------------------------------------------------------
  NUMBER OF       6    SHARED VOTING POWER
    SHARES
 BENEFICIALLY          2,757,510
   OWNED BY       --------------------------------------------------------------
     EACH         7    SOLE DISPOSITIVE POWER
  REPORTING
    PERSON             -0-
     WITH         --------------------------------------------------------------
                  8    SHARED DISPOSITIVE POWER

                       2,757,510
- --------------------------------------------------------------------------------
9   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

    2,757,510
- --------------------------------------------------------------------------------
10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

                                                                            |_|
- --------------------------------------------------------------------------------
11  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

    5.73%
- --------------------------------------------------------------------------------
12  TYPE OF REPORTING PERSON*

- --------------------------------------------------------------------------------
                     *SEE INSTRUCTIONS BEFORE FILLING OUT

                                                               Page 3 of 7 Pages

Item 1.     (a)   Name of Issuer: LEXICON GENETICS, INC.

            (b)   Address of Issuer's Principal Executive Offices:

                  4000 RESEARCH FOREST DRIVE,
                  THE WOODLANDS, TX  77381-4287

Item 2.     (a)   Name of Person Filing:

                  PATRICOF & CO. VENTURES, INC.

            (b)   Address of Principal Business Office or, if none, Residence:

                  445 PARK AVENUE, NEW YORK, NY 10022

            (c)   Citizenship: NEW YORK

            (d)   Title of Class of Securities: COMMON STOCK

            (e)   CUSIP Number: 528872104

Item 3. If this statement is filed pursuant to Rule 13d-1(b) or Rule 3d-2(b) or
        (c), check whether the person filing is a:

      (a)   |_|   Broker or dealer registered under Section 15 of the Act.

      (b)   |_|   Bank as defined in Section 3(a)(6) of the Act.

      (c)   |_|   Insurance company as defined in Section 3(a)(19) of the Act.

      (d)   |_|   Investment company registered under Section 8 of the
                  Investment Company Act of 1940.

      (e)   |_|   An investment adviser in accordance with Rule
                  13d-1(b)(1)(ii)(E).

      (f)   |_|   An employee benefit plan or endowment fund in accordance with
                  Rule 13d-1(b)(1)(ii)(F).

      (g)   |_|   A parent holding company or control person in accordance with
                  Rule 13d-1(b)(1)(ii)(G).

      (h)   |_|   A savings associations as defined in Section 3(b) of the
                  Federal Deposit Insurance Act.

      (i)   |_|   A church plan that is excluded from the definition of an
                  investment company under Section 3(c)(14) of the Investment
                  Company Act of 1940.

      (j)   |_|   Group, in accordance with Rule 13d-1(b)(1)(ii)(J).

                                                               Page 4 of 7 Pages

Item 4. Ownership.

      (a)   Amount beneficially owned: 2,757,510

      (b)   Percent of class: 5.73%

      (c)   Number of shares such person has:

      (i)   Sole power to vote or to direct the vote -0-

      (ii)  Shared power to vote or to direct the vote 2,757,510*

      (iii) Sole power to dispose or to direct the disposition of -0-

      (iv)  Shared power to dispose or to direct the disposition of 2,757,510*

            *SEE RIDER A ATTACHED

Item 5. Ownership of Five Percent or Less of a Class.

            Not applicable

Item 6. Ownership of More than Five Percent on Behalf of Another Person.

            Not applicable.

Item 7. Identification and Classification of the Subsidiary Which Acquired the
        Security Being Reported on By the Parent Holding Company.

            Not applicable.

Item 8. Identification and Classification of Members of the Group.

            Not applicable.

Item 9. Notice of Dissolution of Group.

            Not applicable.

                                                               Page 5 of 7 Pages

Item 10. Certification.

      (a)   The following certification shall be included if the statement is
            filed pursuant to Rule 13d-1(b):

            By signing below I certify that, to the best of my knowledge and
            belief, the securities referred to above were acquired and are held
            in the ordinary course of business and were not acquired and are not
            held for the purpose of or with the effect of changing or
            influencing the control of the issuer of the securities and were not
            acquired and are not held in connection with or as a participant in
            any transaction having that purpose or effect.

      (b)   The following certification shall be included if the statement is
            filed pursuant to Rule 13d-1(c):

            By signing below I certify that, to the best of my knowledge and
            belief, the securities referred to above were not acquired and are
            not held for the purpose of or with the effect of changing or
            influencing the control of the issuer of the securities and were not
            acquired and are not held in connection with or as a participant in
            any transaction having that purpose or effect.

                                                               Page 6 of 7 Pages

                                    SIGNATURE

      After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.

                                          February 14, 2001
                                          -------------------------

                                          /s/ Alan J. Patricof
                                          -------------------------

                                          Alan J. Patricof
                                          -------------------------
                                          Chairman

The original statement shall be signed by each person on whose behalf the
statement is filed or his authorized representative. If the statement is signed
on behalf of a person by his authorized representative (other than an executive
officer or general partner of the filing person), evidence of the
representative's authority to sign on behalf of such person shall be filed with
the statement, provided, however, that a power of attorney for this purpose
which is already on file with the Commission may be incorporated by reference.
The name and any title of each person who signs the statement shall be typed or
printed beneath his signature.

NOTE: Schedules filed in paper format shall include a signed original and five
copies of the schedule, including all exhibits. See Rule 13d-7 for other parties
for whom copies are to be sent.

Attention: Intentional misstatements or omissions of fact constitute Federal
           criminal violations (See 18 U.S.C. 1001)

                                                               Page 7 of 7 Pages
                                     Rider A

As of December 31, 2000, Patricof & Co. Ventures, Inc. ("Patricof") may be
deemed to be the beneficial owner of 1,906,957 shares of common stock (3.96%)
owned by APA Excelsior IV, L.P., a Delaware Limited Partnership ("Excelsior
IV"), 336,463 shares of common stock (0.7%) owned APA Excelsior IV/Offshore,
L.P., a Cayman Islands Limited Partnership ("Offshore"), 477,804 shares of
common stock (1%) owned by the P/A Fund III, L.P., a Pennsylvania Limted
Partnership ("P/A") and 36,286 shares of common stock (0.07%) owned by Patricof
Private Placement Club, L.P., a Delaware Limited Partnership each of such
entities is managed or advised by Patricof and as such, Patricof may be deemed
to have shared voting and dispositive power with the General Partners of each
Partnership with respect to 2,757,510 shares of common stock.