SECURITIES AND EXCHANGE COMMISSION
                              Washington, DC 20549

                                  Schedule 13D

                    Under the Securities Exchange Act of 1934
                               (Amendment No. 4 )*

                          Capital Southwest Corporation
 ------------------------------------------------------------------------------
                                (Name of Issuer)

                             Common $1.00 par value
 ------------------------------------------------------------------------------
                         (Title of Class of Securities)

                                    140501107
                           ---------------------------
                                 (CUSIP Number)

                          William R. Thomas, President
                          Capital Southwest Corporation
          12900 Preston Rd., Suite 700, Dallas, TX 75230 (972) 233-8242
 ------------------------------------------------------------------------------
                  (Name, Address and Telephone Number of Person
                Authorized to Receive Notices and Communications)

                                December 31, 1997
                           --------------------------
                          (Date of Event Which Requires
                            Filing of This Statement)

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
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).

                        (Continued on following page(s))








CUSIP NO. 140501107              Schedule 13D                  Page 2 of 7 Pages



1.   NAME OF REPORTING PERSONS
     S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

               William R. Thomas  ###-##-####
- --------------------------------------------------------------------------------

2.   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
                                                      (a)  [x]
                                                      (b)  [ ]
- --------------------------------------------------------------------------------

3.   SEC USE ONLY


- --------------------------------------------------------------------------------
4.   SOURCE OF FUNDS

               OO
- --------------------------------------------------------------------------------

5.   CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
     ITEMS 2(d) or 2(e)
                                                           [ ]
               Not applicable
- --------------------------------------------------------------------------------

6.   CITIZENSHIP OR PLACE OF ORGANIZATION

               United States of America
- --------------------------------------------------------------------------------

                      7.   SOLE VOTING POWER

                                    607,261
  NUMBER OF           ----------------------------------------------------------
    SHARES
BENEFICIALLY          8.   SHARED VOTING POWER
    OWNED
   BY EACH                          465,531
  REPORTING           ----------------------------------------------------------
   PERSON
    WITH              9.   SOLE DISPOSITIVE POWER

                                    607,261
                      ----------------------------------------------------------

                      10.  SHARED DISPOSITIVE POWER

                                    465,531
                      ----------------------------------------------------------

11.  AGGREGATE AMOUNT BENEFICALLY OWNED BY EACH REPORTING PERSON

               1,072,792
- --------------------------------------------------------------------------------

12.  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES*

               Not applicable                             [ ]
- --------------------------------------------------------------------------------

13.  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

               28.3%
- --------------------------------------------------------------------------------

14.  TYPE OF REPORTING PERSON*

               IN
- --------------------------------------------------------------------------------







CUSIP NO.   140501107   Schedule 13D                           Page 3 of 7 Pages

Item 1.  Security and Issuer.

This  statement  relates  to the  Common  Stock,  $1.00 par value  (the  "Common
Stock"), of Capital Southwest Corporation,  a Texas corporation (the "Company"),
which is a business  development company with executive offices located at 12900
Preston Road, Suite 700, Dallas, Texas, 75230.

Item 2.  Identity and Background.

 This statement is being filed by William R. Thomas,  Thomas  Heritage  Company,
L.L.C., and Thomas Heritage Partners, Ltd., further identified as follows:

(1)      (a)   William R. Thomas

         (b)   Residence address:  7418 Overdale Drive, Dallas, Texas  75240.

         (c)   Present  principal   occupation  is  Chairman  of  the  Board  of
               Directors and  President of the Company,  which is located at the
               address shown in Item 1 above.

         (d)   Mr. Thomas has not been convicted of a criminal proceeding during
               the last five years (excluding minor traffic violations).

         (e)   Mr.  Thomas  has not  been a party  to a  civil  proceeding  of a
               judicial or administrative body of competent  jurisdiction and as
               a result of such  proceeding  was or is  subject  to a  judgment,
               decree  or  final  order  enjoining  future   violations  of,  or
               prohibiting or mandating  activities subject to, federal or state
               securities  laws or finding any  violation  with  respect to such
               laws.

         (f)   Mr. Thomas is a citizen of the Unites States of America.

(2)      (a)   Thomas Heritage Company, L.L.C. ("Thomas LLC")

         (b)   Thomas LLC's  principal  business is to manage and invest  Thomas
               family assets as the general partner of Thomas Heritage Partners,
               Ltd.

         (c)   Thomas LLC is organized as a limited  liability company under the
               laws of the State of Texas.

         (d)   Address of principal office:  7418 Overdale Drive, Dallas, Texas,
               75240.

         (e)   Thomas LLC has not been convicted in a criminal proceeding during
               the last five years.

         (f)   Thomas  LLC has  not  been a party  to a  civil  proceeding  of a
               judicial or administrative body of competent  jurisdiction and as
               a result of such  proceeding  was or is  subject  to a  judgment,
               decree  or  final  order  enjoining  future   violations  of,  or
               prohibiting or mandating  activities subject to, federal or state
               securities  laws or finding any  violation  with  respect to such
               laws.

         (g)   William R. Thomas owns a majority  membership interest and is the
               sole Manager and sole executive officer (President and Secretary)
               of Thomas LLC. See (1)(d) and (e) of Item 2 above.

(3)      (a)   Thomas Heritage Partners, Ltd. ("Thomas Partnership")

         (b)   Thomas  Partnership's  principal business is to manage and invest
               Thomas family assets.

         (c)   Thomas Partnership is organized as a limited partnership under
               the laws of the State of Texas.

         (d)   Address of principal office: 7418 Overdale Drive, Dallas, Texas,
               75240.

         (e)   Neither Thomas Partnership  nor any of its partners have not been
               convicted in a criminal proceeding during the last five years.




CUSIP NO.   140501107        Schedule 13D                      Page 4 of 7 Pages


         (f)  Neither  Thomas  Partnership  nor any of its partners  have been a
              party to a civil proceeding of a judicial or  administrative  body
              of competent  jurisdiction  and as a result of such proceeding was
              or is  subject  to a  judgment,  decree or final  order  enjoining
              future  violations  of, or  prohibiting  or  mandating  activities
              subject  to,  federal  or state  securities  laws or  finding  any
              violation with respect to such laws.

         (g)  Thomas LLC is the sole general partner of Thomas Partnership.  See
              (2) of Item 2 above with respect to Thomas LLC; see (2)(g) of Item
              2 above with respect to the controlling  person of Thomas LLC. The
              remaining  partners of Thomas Partnership are Mr. Thomas and three
              of his  children:  Howard M. Thomas;  William R. Thomas,  III; and
              Suzanne B. Thomas;  each of whom is a citizen of the United States
              of America.  See (1) of Item 2 above with  respect to Mr.  Thomas.
              The residence  addresses and principal  occupations of each of his
              three children are as follows:

              (i)    Howard M. Thomas: principal occupation-investment  banking;
                     residence  address-240  Central Park South, Apt. 14-O,
                     New York, New York, 10019.

              (ii)   William R. Thomas,  III:  principal  occupation-Air  Force
                     officer;  permanent residence address-7418 Overdale Drive,
                     Dallas, Texas, 75240.

              (iii)  Suzanne   B.   Thomas:   principal   occupation-student;
                     permanent residence address-7418 Overdale Drive, Dallas,
                     Texas, 75240.


Item 3.  Source and Amount of Funds or Other Consideration.

Mr. Thomas owns of record and beneficially 327,725 shares of Common Stock, which
have been purchased by Mr. Thomas or distributed by the Company's employee stock
ownership plans during the term of his employment  with the Company,  commencing
in 1962.  The sources of funds for the  purchases of such  Shares,  exclusive of
funds distributed by the employee stock ownership plans, have been a combination
of personal funds, commercial bank loans and broker-dealer margin account loans.
A commercial bank loan to the undersigned in the principal  amount of $2,600,000
as of the date  hereof  was a source  of part of the funds  used in making  such
purchases. The bank loan, which was made in the ordinary course of business by a
commercial bank, is secured by 280,000 shares of Common Stock,  which shares are
beneficially  owned  by the  undersigned.  The  bank  loan  is in the  form of a
promissory  note due  March  31,  1998,  which has been  renewed  with  periodic
principal  reductions and increases for successive periods since 1976,  although
the  commercial  bank holding the note is not obligated to do so and may instead
elect to require repayment of the note. The broker-dealer margin account loan is
secured by 3,900  shares of common stock and by shares of another  issuer.  This
margin  account loan was  initiated on November 18, 1997 and has been  increased
since that date to $311,857 as of December 31, 1997.

See Item 5 below for a  description  of  certain  other  shares of Common  stock
deemed to be beneficially owned by Mr. Thomas.

Thomas  Partnership  owns of record and  beneficially  206,525  shares of Common
Stock,  which were contributed to Thomas  Partnership in May 1995 by Thomas LLC,
Mr.  Thomas,  and three of his  children  in  exchange  for  general and limited
partnership interests in Thomas Partnership.


Item 4.  Purpose of Transaction.

The  shares  of Common  Stock  owned of record  by the  reporting  persons  were
acquired as an investment and for the purpose of maintaining  the control of the
Company  by its  present  management,  of which Mr.  Thomas is a part and,  with
respect to Thomas  Partnership,  holding  such  shares as an  investment  of the
Thomas  family.  See Item 5 below for a  description  of certain other shares of
Common Stock deemed to be beneficially owned by Mr. Thomas.





CUSIP NO.   140501107       Schedule 13D                       Page 5 of 7 Pages



The  reporting  persons have no present  plans or proposals  regarding  mergers,
reorganizations  or  liquidation  of the  Company;  the sale or  transfer of the
assets of the  Company;  changes  in the  Company's  management;  changes in the
Company's business or corporate structure;  changes in the Company's Articles of
Incorporation,  By-Laws or other  similar  instrument;  withdrawal on The Nasdaq
Stock Market of the Common Stock;  terminating  the Common Stock's  registration
pursuant to Section  12(g)(4) of the  Securities  Exchange Act of 1934; or other
similar actions.

Item 5.  Interest in Securities of the Issuer.

The  interest of the  reporting  persons in the Common  stock as of December 31,
1997 is set forth below:

(1)      William R. Thomas is the record and/or beneficial owner of shares of 
         Common Stock as follows:

         (a)  Record and  beneficial  owner of 327,725  shares of Common  Stock
              over which Mr.  Thomas has sole  voting and dispositive power.

         (b)  Beneficial  owner  of 700  shares  of  Common  Stock  held  by the
              Individual  Retirement Account of William R. Thomas and over which
              Mr. Thomas has sole voting and dispositive power.

         (c)  Beneficial  owner of 206,525 shares of Common Stock held of record
              by Thomas  Partnership  over which Mr.  Thomas has sole voting and
              dispositive  power  as  the  holder  of  the  majority  membership
              interest,  sole Manager, and sole executive officer of Thomas LLC,
              the sole general partner of Thomas Partnership. As of December 31,
              1997,  Mr.  Thomas  also  directly  held a 50.7%  limited  partner
              interest in Thomas Partnership.

         (d)  Beneficial  owner of 72,311 shares of Common Stock held by members
              of Mr.  Thomas's  immediate  family and over which Mr.  Thomas has
              sole voting and dispositive power.

         (e)  Mr.  Thomas  and J.  Bruce  Duty,  Senior  Vice  President  of the
              Company, together constitute a majority of the trustees of certain
              trusts pursuant to employee stock ownership plans for employees of
              the  Company  and its  wholly-owned  subsidiaries  owning  377,387
              shares of Common Stock. Messrs. Thomas and Duty have shared voting
              and dispositive power over such shares.  Mr. Thomas is, therefore,
              deemed to beneficially own such shares.

         (f)  Messrs.  Thomas  and Duty  participate  in the power to direct the
              trustees in the voting of 88,144  shares of Common  Stock owned by
              trusts pursuant to a pension plan for employees of the Company and
              certain wholly-owned  subsidiaries of the Company.  Messrs. Thomas
              and Duty  have  shared  voting  and  dispositive  power  over such
              shares. Mr. Thomas is, therefore,  deemed to beneficially own such
              shares.

         The  total  number  of  shares  owned of  record  or deemed to be owned
         beneficially by Mr. Thomas is 1,072,792, which constitutes 28.3% of the
         issued and outstanding shares of Common Stock.

(2)      Thomas LLC is the beneficial owner of 206,525 shares of Common Stock as
         the sole  general  partner of Thomas  Partnership  with a 1.3%  general
         partner interest.  Thomas LLC has sole voting and investment power over
         such shares,  which is exercised by Mr. Thomas as its majority  member,
         sole Manager, and sole executive officer. The shares deemed to be owned
         beneficially   by  Thomas  LLC  constitute   5.5%  of  the  issued  and
         outstanding  shares of Common Stock. As indicated  above, Mr. Thomas is
         the  ultimate  beneficial  owner of such  shares  (see (1)(c) of Item 5
         above).

(3)      Thomas Partnership is the record and beneficial owner of 206,525 shares
         of Common  Stock.  Thomas  Partnership  has sole voting and  investment
         power over such shares, which is exercised by its sole general partner,
         Thomas LLC. The shares owned of record by Thomas Partnership constitute
         5.5% of the issued and outstanding shares of Common Stock. As indicated
         above, Mr. Thomas is the ultimate  beneficial owner of such shares (see
         (1)(c) of Item 5 above).




CUSIP NO.   140501107         Schedule 13D                     Page 6 of 7 Pages



During  the sixty  days  preceding  the date of this  statement,  the  reporting
persons have effected the following transactions in shares of Common Stock:

                                                                                    

            Date of               Shares            Shares          Price          Character of Transaction/
          Transaction            Acquired          Disposed       Per Share             Consideration
          -----------            --------          --------       ---------             -------------
      William R. Thomas:

           11/17/97               14,000                         $39.1875         Exercise of incentive stock option

           11/17/97                100                           $78.00           Open market purchase

           11/18/97                400                           $78.00           Open market purchase

           11/21/97               1,500                          $78.75           Open market purchase

            12/1/97               2,000                          $80.25           Open market purchase

            12/4/97                352                           $81.75           Acquired by Mr. Thomas' children through
                                                                                  the Company's dividend reinvestment plan

The above table does not include certain distributions and purchase transactions in the ordinary course of business effected by the trusts described in (1)(e) of Item 5 above. Except for the group comprised solely of the reporting persons, each of the reporting persons disclaims that he or it is a member of a group for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended ("Act"). Pursuant to Rule 13d-4 under the Act, each of the reporting persons hereby expressly declares that the filing of this Schedule 13D shall not be construed as an admission that any such reporting person is, for the purposes of Section 13(d) or 13(g) of the Act, the beneficial owner of the shares of Common Stock listed, and each reporting person expressly disclaims that he or it is the beneficial owner of any such shares, other than shares owned of record by such reporting person. Item 6. Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer. Except for Mr. Thomas' position as a trustee of certain employee stock ownership plans of the Company and its wholly-owned subsidiaries as described in (1)(e) of Item 5 above, the reporting persons do not have any contracts, arrangements, understandings or relationships with any person with respect to any securities of the Company regarding the transfer or voting of such securities, finders fees, joint ventures, loan or option arrangements, puts or calls, guarantees of profits, division of profits or loss, or giving or withholding of proxies. Item 7. Material to be Filed as Exhibits. Not applicable. CUSIP NO. 140501107 Schedule 13D Page 7 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. /s/ William R. Thomas ---------------------------------------------- DATE: January 22, 1998 William R. Thomas