SECURITIES AND EXCHANGE COMMISSION
                     Washington, D.C.  20549
                                
                                                
                          SCHEDULE 13D
                       (Amendment No. 31)
                                
                                                
            Under the Securities Exchange Act of 1934
                                 
                        IDEX CORPORATION                
                        (Name of Issuer)
                                
                        
             Common Stock Par Value $0.01 Per Share     
                (Title of Class and Securities) 
                                
                                                
                           45167R104                  
              (CUSIP Number of Class of Securities)
                                                
                                                
                                                
              James E. McKee, Gabelli Funds, Inc.,
 One Corporate Center, Rye, New York 10580-1434, (914) 921-5067
    (Name, Address and Telephone Number of Person Authorized
             to Receive Notices and Communications)
                                
                                                
                         June 24, 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 State-
ment because of Rule 13d-1(b)(3) or (4), check the following box:
                                                        ____     
                                                       /___/ 

                                                       
                                                      

_________________________________________________________________

CUSIP No. 45167R104                                        13D
_________________________________________________________________
(1)  NAMES OF REPORTING PERSONS 
      S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS
      Gabelli Funds, Inc.            I.D. No. 13-3056041
_________________________________________________________________
(2)  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:
                                                       ____
                                                  (a) /___/
                                                       ____
                                                  (b) /___/
_________________________________________________________________
(3)  SEC USE ONLY
_________________________________________________________________
(4)  SOURCE OF FUNDS*
      00: Funds of investment company clients
_________________________________________________________________
(5)  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS
     REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)          _____
                                                     /   /
_________________________________________________________________
(6)  CITIZENSHIP OR PLACE OF ORGANIZATION
      New York
_________________________________________________________________ 
                                        : (7) SOLE VOTING POWER
                                        :     972,050 (Item 5)
                                        :________________________
                                        : (8) SHARED VOTING POWER
 NUMBER OF SHARES BENEFICIALLY          :     None    (Item 5) 
 OWNED BY EACH REPORTING                :________________________
 PERSON WITH                            : (9) SOLE DISPOSITIVE 
                                        :     POWER
                                        :     972,050 (Item 5)
                                        :________________________
                                        :(10) SHARED DISPOSITIVE 
                                        :     POWER
                                        :     None    (Item 5)  
_________________________________________________________________
(11) AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
     972,050   (Item 5)
_________________________________________________________________
(12) CHECK BOX IF THE AGGREGATE AMOUNT IN ROW 11
     EXCLUDES CERTAIN SHARES*                         _____
                                                     /  x /
_________________________________________________________________
(13) PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 11
      3.33%
_________________________________________________________________
(14) TYPE OF REPORTING PERSON*
      HC, IA, CO
_________________________________________________________________
              *SEE INSTRUCTIONS BEFORE FILLING OUT!  

________________________________________________________________

CUSIP No. 45167R104                                        13D
_________________________________________________________________
(1)  NAMES OF REPORTING PERSONS 
      S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS
      GAMCO Investors, Inc.              I.D. No. 13-2951242
_________________________________________________________________
(2)  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:
                                                       ____
                                                  (a) /___/
                                                       ____
                                                  (b) /___/
_________________________________________________________________
(3)  SEC USE ONLY
_________________________________________________________________
(4)  SOURCE OF FUNDS*
      OO:  Funds of investment advisory clients
_________________________________________________________________
(5)  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS
     REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)         ____
                                                     /x___/
_________________________________________________________________
(6)  CITIZENSHIP OR PLACE OF ORGANIZATION
      New York
_________________________________________________________________ 
                                        : (7) SOLE VOTING POWER
                                        :     1,660,847 (Item 5)
                                        :________________________
                                        : (8) SHARED VOTING POWER
 NUMBER OF SHARES BENEFICIALLY          :     None 
 OWNED BY EACH REPORTING                :________________________ 
 PERSON WITH                            : (9) SOLE DISPOSITIVE 
                                        :     POWER
                                        :     1,714,097 (Item 5)
                                        :________________________ 
                                        :(10) SHARED DISPOSITIVE 
                                        :     POWER
                                        :     None  
_________________________________________________________________
(11) AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
      1,714,097 (Item 5)
_________________________________________________________________

(12) CHECK BOX IF THE AGGREGATE AMOUNT IN ROW 11
     EXCLUDES CERTAIN SHARES*                        ____
                                                     /___/
_________________________________________________________________
(13) PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 11
      5.87%      
________________________________________________________
(14) TYPE OF REPORTING PERSON*
      IA, CO
_________________________________________________________________
              *SEE INSTRUCTIONS BEFORE FILLING OUT!   

_________________________________________________________________

CUSIP No. 45167R104                                        13D
_________________________________________________________________
(1)  NAMES OF REPORTING PERSONS 
      S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS
      Gabelli Asset Management Company International Advisory     
      Services Ltd. 
_________________________________________________________________
(2)  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:
                                                       ____
                                                  (a) /___/
                                                       ____
                                                  (b) /___/
_________________________________________________________________
(3)  SEC USE ONLY
_________________________________________________________________
(4)  SOURCE OF FUNDS*
      00-Funds of clients
_________________________________________________________________
(5)  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS
     REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)          ____
                                                     /___/
_________________________________________________________________
(6)  CITIZENSHIP OR PLACE OF ORGANIZATION
      Bermuda                     
_________________________________________________________________ 
                                        : (7) SOLE VOTING POWER
                                        :     1,500 (Item 5)
                                        :________________________
                                        : (8) SHARED VOTING POWER
 NUMBER OF SHARES BENEFICIALLY          :     None  
 OWNED BY EACH REPORTING                :________________________ 
 PERSON WITH                            : (9) SOLE DISPOSITIVE 
                                        :     POWER
                                        :     1,500 (Item 5)
                                        :________________________ 
                                        :(10) SHARED DISPOSITIVE 
                                        :     POWER
                                        :     None  
_________________________________________________________________
(11) AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
      1,500 (Item 5)
_________________________________________________________________
(12) CHECK BOX IF THE AGGREGATE AMOUNT IN ROW 11
     EXCLUDES CERTAIN SHARES*                         ____
                                                     /___/
_________________________________________________________________
(13) PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 11
      0.01%
_________________________________________________________________
(14) TYPE OF REPORTING PERSON*
      CO
_________________________________________________________________

_________________________________________________________________
_________________________________________________________________

CUSIP No. 45167R104                                        13D
_________________________________________________________________
(1)  NAMES OF REPORTING PERSONS 
      S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS
      Gabelli & Company, Inc.            I.D. No. 13-2885006
_________________________________________________________________
(2)  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:
                                                       ____
                                                  (a) /___/
                                                       ____
                                                  (b) /___/
_________________________________________________________________
(3)  SEC USE ONLY
_________________________________________________________________
(4)  SOURCE OF FUNDS*
      WC                    
_________________________________________________________________
(5)  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS
     REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)          ______
                                                     /  X  /
_________________________________________________________________
(6)  CITIZENSHIP OR PLACE OF ORGANIZATION
      New York
_________________________________________________________________ 
                                        : (7) SOLE VOTING POWER
                                        :     200   (Item 5)
                                        :________________________
                                        : (8) SHARED VOTING POWER
 NUMBER OF SHARES BENEFICIALLY          :     None  (Item 5)
 OWNED BY EACH REPORTING                :________________________ 
 PERSON WITH                            : (9) SOLE DISPOSITIVE 
                                        :     POWER
                                        :     200   (Item 5)
                                        :________________________ 
                                        :(10) SHARED DISPOSITIVE 
                                        :     POWER
                                        :     None  (Item 5)
_________________________________________________________________
(11) AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
     200  (Item 5)
_________________________________________________________________
(12) CHECK BOX IF THE AGGREGATE AMOUNT IN ROW 11
     EXCLUDES CERTAIN SHARES*                         ____
                                                     /___/
_________________________________________________________________
(13) PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 11
      0.00%
_________________________________________________________________
(14) TYPE OF REPORTING PERSON*
      BD, CO
_________________________________________________________________
              *SEE INSTRUCTIONS BEFORE FILLING OUT!  
________________________________________________________________

CUSIP No. 45167R104                                        13D
_________________________________________________________________
(1)  NAMES OF REPORTING PERSONS 
     S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS
     Mario J. Gabelli                  I.D. No. ###-##-####
_________________________________________________________________ 
(2)  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:
                                                       ____
                                                  (a) /___/
                                                       ____
                                                  (b) /___/
_________________________________________________________________
(3)  SEC USE ONLY
_________________________________________________________________
(4)  SOURCE OF FUNDS*
     None
_________________________________________________________________
(5)  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS
     REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)          ____
                                                     /   /
_________________________________________________________________
(6)  CITIZENSHIP OR PLACE OF ORGANIZATION
      USA 
_________________________________________________________________ 
                                        : (7) SOLE VOTING POWER
                                        :     None (Item 5)
                                        :________________________
                                        : (8) SHARED VOTING POWER
 NUMBER OF SHARES BENEFICIALLY          :     None  
 OWNED BY EACH REPORTING                :________________________ 
 PERSON WITH                            : (9) SOLE DISPOSITIVE 
                                        :     POWER
                                        :     None (Item 5)
                                        :________________________ 
                                        :(10) SHARED DISPOSITIVE 
                                        :     POWER
                                        :     None  
_________________________________________________________________
(11) AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
     None (Item 5)
_________________________________________________________________
(12) CHECK BOX IF THE AGGREGATE AMOUNT IN ROW 11
     EXCLUDES CERTAIN SHARES*                         _____
                                                     /  x /
_________________________________________________________________
(13) PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 11
      0.00%
_________________________________________________________________
(14) TYPE OF REPORTING PERSON*
      IN
_________________________________________________________________

              *SEE INSTRUCTIONS BEFORE FILLING OUT!
Item 1.Security and Issuer

          This Amendment No. 31 to Schedule 13D on the Common 

Stock of IDEX Corporation (the "Issuer") is being filed on behalf
of the undersigned to amend the Schedule 13D, as amended (the
"Schedule 13D") which was originally filed on June 16, 1989. 
Unless otherwise indicated, all capitalized terms used herein but
not defined herein shall have the same meaning as set forth in
the Schedule 13D  

Item 2.   Identity and Background
          This statement is being filed by Mario J. Gabelli ("Mr.
Gabelli") and various entities which he directly or indirectly
controls or for which he acts as chief investment officer.  These
entities, except for Lynch Corporation ("Lynch"), Spinnaker
Industries, Incorporated ("Spinnaker"), Western New Mexico
Telephone Company ("Western New Mexico"), Entoleter, Inc.
("Entoleter"),  Lynch Telecommunications Corporation ("Lynch
Telecom"), Lynch Telephone Corporation ("Lynch Telephone") and
Inter-Community Telephone Company ("Inter-Community")
(collectively, "Lynch and its affiliates"), engage in various
aspects of the securities business, primarily as investment
adviser to various institutional and individual clients, includ-
ing registered investment companies and pension plans, as
broker/dealer and as general partner of various private invest-
ment partnerships.  Certain of these entities may also make
investments for their own accounts. 
          The foregoing persons in the aggregate often own
beneficially more than 5% of a class of equity securities of a
particular issuer.  Although several of the foregoing persons are
treated as institutional investors for purposes of reporting
their beneficial ownership on the short-form Schedule 13G, the
holdings of those who do not qualify as institutional investors
may exceed the 1% threshold presented for filing on Schedule 13D
or implementation of their investment philosophy may from time to
time require action which could be viewed as not completely
passive.  In order to avoid any question as to whether their
beneficial ownership is being reported on the proper form and in
order to provide greater investment flexibility and administra-
tive uniformity, these persons have decided to file their benefi-
cial ownership reports on the more detailed Schedule 13D form
rather than on the short-form Schedule 13G and thereby to provide
more expansive disclosure than may be necessary. 
          (a), (b) and (c) - This statement is being filed by one
or more of the following persons: Gabelli Funds, Inc. ("GFI"),
GAMCO Investors, Inc. ("GAMCO"), Gabelli Securities, Inc.
("GSI"), Gabelli & Company, Inc. ("Gabelli & Company"), Gabelli
Performance Partnership L.P. ("GPP"), GLI, Inc. ("GLI"), Gabelli
Associates Fund ("Gabelli Associates"), Gabelli Associates
Limited ("GAL"), Gabelli & Company, Inc. Profit Sharing Plan (the
"Plan"), Gabelli International Limited ("GIL"), Gabelli Interna-
tional II Limited ("GIL II"), Gabelli International Gold Fund
Limited ("GIGFL"), ALCE Partners, L.P. ("ALCE"), Gabelli
Multimedia Partners, L.P. ("Multimedia Partners"), Gabelli Asset
Management Company International Advisory Services Ltd.
("GIASL"),Gabelli Foundation, Inc. ("Foundation"), Mr. Gabelli,
Lynch, Spinnaker, Western New Mexico, Entoleter, Lynch Telecom,
Lynch Telephone and Inter-Community. Those of the foregoing
persons signing this Schedule 13D are hereafter referred to as
the "Reporting Persons". 
          GAMCO, a wholly-owned subsidiary of GFI, is an
investment adviser registered under the Investment Advisers Act
of 1940, as amended ("Advisers Act").  GAMCO is an investment
manager providing discretionary managed account services in the
equity area for employee benefit plans, private investors,
endowments and foundations. 
          Gabelli & Company, a wholly-owned subsidiary of GSI, is
a broker-dealer registered under the Securities Exchange Act of
1934, as amended ("l934 Act"), which as a part of its business
regularly purchases and sells securities for its own account.  
          GLI, a wholly-owned subsidiary of GSI, is the trustee
for the Gabelli-Rosenthal & Partners, L.P. Liquidating Trust.
          Gabelli Associates is a New York limited partnership
whose primary business purpose is risk arbitrage investments. 
GSI and Mr. Gabelli are the general partners of Gabelli As-
sociates. 
          GAL is a corporation whose primary business purpose is 
risk arbitrage investments.  Shares of GAL's Common Stock will be
offered to persons who are neither citizens nor residents of the 
United States and may be offered to a limited number of U.S.
investors.  GSI is the investment manager of GAL.
          GSI, a majority-owned subsidiary of GFI, is a Delaware 
corporation which as a part of its business regularly purchases
and sells securities for its own account.  It is the immediate
parent of Gabelli & Company.  
          GFI is the ultimate parent company for a variety of
companies engaged in the securities business, each of which is
named above.  In addition, GFI is an investment adviser
registered under the Advisers Act.  GFI is an investment adviser
which presently provides discretionary managed account services
for The Gabelli Equity Trust Inc., The Gabelli Asset Fund, The
Gabelli Growth Fund, The Gabelli Convertible Securities Fund,
Inc., The Gabelli Value Fund Inc., The Gabelli Small Cap Growth
Fund, The Gabelli Equity Income Fund, The Gabelli ABC Fund, The
Gabelli Global Telecommunications Fund, Gabelli Gold Fund, Inc.,
The Gabelli Global Multimedia Trust Inc., The Gabelli Global
Convertible Securities Fund, Gabelli Capital Asset Fund, Gabelli 
International Growth Fund, Inc. and The Gabelli Global
Interactive Couch Potato Fund (collectively, the "Funds"), which
are registered investment companies.
          The Plan, a qualified employee profit sharing plan,
covers substantially all employees of GFI and its affiliates. 
          GPP, a Delaware limited partnership, is a limited
partnership whose primary business purpose is investing in
securities.  Mr. Gabelli is the general partner and chief invest-
ment officer of GPP. 
          GIL is a corporation whose primary business purpose is 
investing in a portfolio of equity securities and securities
convertible into, or exchangeable for, equity securities in order
to achieve its investment objective of significant long-term
growth of capital.  Shares of GIL's common stock are offered to
persons who are neither citizens nor residents of the United
States and may be offered to a limited number of U.S. investors. 
The investments of GIL are managed by Mr. Gabelli who is also a
director and Chairman of the Board of Directors of GIL.
          GIL II is a corporation whose business purpose is
investing primarily in a portfolio of equity securities and
securities convertible into, or exchangeable for, equity securit-
ies in order to achieve its investment objective of significant
long-term growth of capital.  Shares of GIL II's common stock are
offered to persons who are neither citizens nor residents of the 
United States and may be offered to a limited number of U.S.
investors.  The investments of GIL II are managed by Mr. Gabelli 
who is also a director and Chairman of the Board of Directors of 
GIL II.
       ALCE is a Delaware investment limited partnership that
seeks long-term capital appreciation primarily through
investments in public and private equity securities.  GSI is a
general partner of ALCE.
       Multimedia Partners is a Delaware investment limited
partnership whose objective is to provide long-term capital
appreciation by investing primarily in public and private
multimedia communications companies.  GSI is a general partner of
Multimedia Partners.
       GIASL is a corporation whose primary business purpose is
to provide advisory services to offshore funds.
       The Foundation is a private foundation. Mr. Gabelli is the
President, a Trustee and the Investment Manager of the
Foundation.
       Lynch, an Indiana corporation, is a diversified public
company traded on the American Stock Exchange.  Its subsidiaries 
are engaged in communications, services, and manufactured pro-
ducts.  Spinnaker, a Delaware subsidiary of Lynch, is also a
public company and its stock is traded through the NASDAQ System. 
Spinnaker is a diversified manufacturing firm with major
subsidiaries in specialty adhesive-backed materials business. 
Another of Lynch's subsidiaries, Western New Mexico, provides
telephone services in a service area in Southwestern New Mexico. 
Inter-Community, which is also a subsidiary of Lynch, provides
local telephone services in an area 40 miles west of Fargo, North
Dakota.   Lynch and Spinnaker actively pursue new business ven-
tures and acquisitions.  Lynch and its affiliates make invest-
ments in marketable securities to preserve capital and maintain
liquidity for financing their business activities and
acquisitions (not in the case of Western New Mexico) and are not
engaged in the business of investing, reinvesting, or trading in
securities.  Mr. Gabelli is Chairman of Lynch and owns
beneficially 23.52% of the shares of common stock of Lynch. 
          Mr. Gabelli is the majority stockholder and Chairman of
the Board of Directors and Chief Executive Officer of GFI and the
Chief Investment Officer for each of the Reporting Persons other
than GIASL.  GFI, in turn, is the sole stockholder of GAMCO.  GFI
is also the majority stockholder of GSI.  Gabelli & Company is a
wholly-owned subsidiary of GSI.  GLI is a wholly-owned subsidiary
of GSI.
          The Reporting Persons do not admit that they constitute
a group. 
          GFI, GAMCO, Gabelli & Company and GLI are New York
corporations and GSI is a Delaware corporation, each having its
principal business office at One Corporate Center, Rye, New York 
10580-1434. GPP is a Delaware limited partnership having its
principal business office at 8 Sound Shore Drive, Greenwich,
Connecticut 06830.  Gabelli Associates is a New York limited
partnership having its principal business office at One Corporate
Center, Rye, New York 10580-1434. GAL and GIL are corporations
organized under the laws of the British Virgin Islands having
their principal business office at c/o MeesPierson (Cayman)
Limited, British American Centre, Dr. Roy's Drive-Phase 3, George
Town, Grand Cayman, British West Indies.  GIL II is a corporation
organized under the laws of the British Virgin Islands having
their principal business office at c/o Coutts & Company (Cayman)
Limited, West Bay Road, Grand Cayman, British West Indies.  GIASL
is a Bermuda corporation with its principal business office at
c/o Appleby, Spurling & Kempe, Cedar House, 41 Cedar Avenue,
Hamilton HM12, Bermuda.  The Foundation is a private foundation
having its principal offices at 165 West Liberty Street, Reno,
Nevada 89501.
Lynch is an Indiana corporation having its principal business
office at 8 Sound Shore Drive, Greenwich, CT 06830.  Spinnaker is
a Delaware corporation having its principal business office at
251 Welton Street, Hamden, CT 06511. 
          For information required by instruction C to Schedule
13D with respect to the executive officers and directors of the
foregoing entities and other related persons (collectively,
"Covered Persons"), reference is made to Schedule I annexed
hereto and incorporated herein by reference. 
          (d) and (e) -  On December 8, 1994, the SEC instituted 
and simultaneously accepted offers for the settlement of an
administrative proceeding against Gabelli & Company and GAMCO. 
The order instituting the proceeding included a finding, which
Gabelli & Company and GAMCO neither admitted nor denied, that
they failed to implement and maintain policies and procedures
reasonably designed to prevent the misuse of material, nonpublic
information by not sepecifically addressing the special
circumstances that arose from their affiliation with Lynch
Corporation, a public company.  To resolve this matter, Gabelli &
Company and GAMCO agreed to cease and desist from violating
Section 15(f) of the 1934 Act and Section 204A of the Advisers
Act, respectively.  They further agreed to each pay a civil
penalty in the amount of $50,000, and to retain, and adopt the
recommendations of, an independant consultant regarding their
Section 15(f) and Section 204A policies and procedures.  
     (f) - Reference is made to Schedule I hereto.  

Item 5.   Interest In Securities Of The Issuer
          (a)  The aggregate number and percentage of Securities
to which this Schedule 13D relates is 2,687,847 shares, repre-
senting 9.21% of the 29,170,699 shares outstanding as reported in
the most recently filed Form 10-Q for the quarter ended March 31,
1997.  The Reporting Persons beneficially own those Securities as
follows: 








                         Shares of           % of                
                          Common             Class of
Name                     Stock               Common  

GAMCO 
  As Principal                  0                0.00%
  As Agent              1,714,097                5.87%

GFI
  As Principal                  0                0.00%
  As Agent                972,050                3.33%

GIASL                       1,000                0.01%

Gabelli & Company             200                0.00%

Mr. Gabelli                     0                0.00% 

           Mr. Gabelli is deemed to have beneficial ownership of
the Securities owned beneficially by each of the foregoing
persons and GFI is deemed to have beneficial ownership of the
securities owned beneficially by each of the foregoing persons
other than Mr. Gabelli. 
          (b) Each of the Reporting Persons and Covered Persons has
the sole power to vote or direct the vote and sole power to dispose
or to direct the disposition of the Securities reported for it,
either for its own benefit or for the benefit of its investment
clients or its partners, as the case may be, except that GAMCO
Investors, Inc. does not have authority to vote 53,250 of the
reported shares, and except that GFI has sole dispositive and
voting power with respect to the 972,050 shares of the Issuer held
by the the Funds, so long as the aggregate voting interest of all
joint filers does not exceed 25% of their total voting interest in
the Issuer and in that event, the Proxy Voting Committee of each of
the Funds shall respectively vote that Fund's shares, and except
that, at any time, the Proxy Voting Committee of each such Fund may
take and exercise in its sole discretion the entire voting power
with respect to the shares held by such Fund under special
circumstances such as regulatory considerations, and except that
the power of Mr. Gabelli and GFI is indirect with respect to
Securities beneficially owned directly by other Reporting Persons. 
          (c) Information with respect to all transactions in the
Securities which were effected during the past sixty days by each
of the Reporting Persons and Covered Persons is set forth on
Schedule II annexed hereto and incorporated herein by reference. 





















Signature
            After reasonable inquiry and to the best of my know-
ledge and belief, I certify that the information set forth in this
statement is true, complete and correct. 
Dated:    June 27, 1997

                                   GABELLI FUNDS, INC.



                                   By:_________________________
                                      James E. McKee
                                      General Counsel

               
                                   GAMCO INVESTORS, INC.  
                                   
                                        
                                   By:_________________________
                                      Douglas R. Jamieson  
                                      Executive Vice President
                                   


                                   GABELLI ASSET MANAGEMENT COMPANY
                                   INTERNATIONAL ADVISORY SERVICES
                                   LIMITED


                                   By:__________________________
                                      Marc J. Gabelli
                                      Director
                                      by: James E. McKee
                                      Attorney-in-Fact


                                   Mario J. Gabelli


                                   By:____________________________
                                      James E. McKee
                                      Attorney-in-Fact



Schedule I


              Information with Respect to Executive
            Officers and Directors of the Undersigned 

          Schedule I to Schedule 13D is amended, in pertinent part, as
follows:
          The following sets forth as to each of the executive officers
and directors of the undersigned: his name; his business address; and
his present principal occupation or employment and the name, principal
business and address of any corporation or other organization in which
such employment is conducted.  Unless otherwise specified, the principal
employer of each such individual is Gabelli Funds, Inc., Gabelli &
Company, Inc., or GAMCO Investors, Inc., the business address of each of
which is One Corporate Center, Rye, New York 10580, and each such
individual identified below is a citizen of the United States.  To the
knowledge of the undersigned, during the last five years, no such person
has been convicted in a criminal proceeding (excluding traffic
violations or similar misdemeanors), and no such person was a party to
a civil proceeding of a judicial or administrative body of competent
jurisdiction as a result of which he 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 law or
finding any violation with respect to such laws except as reported in
Item 2(d) of this Schedule 13D. 


Gabelli Funds, Inc. 

Directors: 

     Mario J. Gabelli*

     Richard B. Black              Chairman of Raster Image
                                   Processing Systems; Chairman
                                   ECRM; Director of Archetype
                                   and Oak Technology; Director
                                   of The Morgan Group, Inc.;
                                   General Partner of KBA Part-  
                                   ners, Parker Plaza
                                   400 Kelby Street,
                                   Fort Lee, NJ 07029

     Charles C. Baum               Chairman, Director and Chief
                                   Executive Officer of The Morgan
                                   Group, Inc.;
                                   Secretary & Treasurer
                                   United Holdings              
                                   2545 Wilkens Avenue
                                   Baltimore, MD  21223

     Dr. Eamon M. Kelly            President
                                   Tulane University
                                   218 Gibson Hall
                                   6823 St. Charles Avenue
                                   New Orleans, LA  70118

     Marc J. Gabelli               Vice President


Officers:

     Mario J. Gabelli              Chairman, Chief Executive
                                   Officer and Chief Investment
                                   Officer
     
     Stephen G. Bondi              Executive Vice President,
                                   Chief Financial and Admin-
                                   istrative Officer                  
                         
     James E. McKee                Vice President, General 
                                   Counsel and Secretary

_____________________

     *    Mr. Gabelli is the Chairman, Chief Executive Officer and Chief
Investment Officer of Gabelli Funds, Inc. and of GAMCO Investors, Inc.;
Director/Trustee of all registered investment companies advised by
Gabelli Funds, Inc.; Chairman and Chief Executive Officer of Lynch
Corporation. 

GAMCO Investors, Inc.

Directors:
     
     Mario J. Gabelli
     Douglas R. Jamieson
     Joseph R. Rindler, Jr.
     Regina M. Pitaro
     F. William Scholz, II

Officers:
     
     Mario J. Gabelli              Chief Executive Officer 
                                   and Chief Investment Officer

     Joseph R. Rindler, Jr.        Chairman

     Douglas R. Jamieson           Executive Vice President 

     Stephen G. Bondi              Vice President

     James E. McKee                Vice President, General Counsel
                                   and Secretary


Gabelli Securities, Inc.

Directors:

     Robert W. Blake               President of W.R. Blake
                                   & Sons, Inc.
                                   196-20 Northern Boulevard
                                   Flushing, NY  11358

     Douglas G. DeVivo             General Partner of ALCE
                                   Partners, L.P.
                                   One First Street, Suite 16
                                   Los Altos, CA  94022

     Ronald L. Gallatin            Consultant
                                   Gabelli Securities, Inc.
                                   One Corporate Center
                                   Rye, NY  10580

     Francine Sommer               Chief Executive Officer of
                                   General Partner of Gabelli
                                   Multimedia Partners, L.P.
                                   One Corporate Center
                                   Rye, NY  10580

     Joseph R. Rindler, Jr.        See above








Officers:
     
     Gary P. Watson                Executive Vice President,
                                   Chief Financial and Admin-
                                   istrative Officer


     Stephen G. Bondi              Vice President

     James E. McKee                Secretary


Gabelli & Company, Inc.

Directors:

     James G. Webster, III         Chairman 
     
     Stephen G. Bondi              See above

     Donald C. Jenkins             Director of Research

Officers:

     James G. Webster, III         Chairman 

     Stephen G. Bondi              Vice President 

     Walter K. Walsh               Compliance Officer

     James E. McKee                Secretary


GLI, Inc.
Directors:

     Mario J. Gabelli              See above-Gabelli Funds, Inc.


Officers:

     Mario J. Gabelli              Chairman and Chief Investment
                                   Officer

     Stephen G. Bondi              Vice President


Gabelli Associates Limited

Directors:

     Mario J. Gabelli              See above-Gabelli Funds, Inc.
     
     MeesPierson  (Cayman)         British American Centre   
     Limited                       Dr. Roy's Drive- Phase 3
                                   Georgetown, Grand Cayman   
                                   Cayman Islands, British             
                                   WestIndies

Officers:

     Mario J. Gabelli              Chief Investment Officer

     Kevin Bromley                 Vice President, Treasurer and
                                   Assistant Secretary

     Sandra Wight                  Secretary and Assistant Treasurer


Gabelli International Limited

Directors:

     Mario J. Gabelli              See above-Gabelli Funds, Inc.
   
     MeesPierson  (Cayman)         British American Centre   
     Limited                       Dr. Roy's Drive- Phase 3
                                   Georgetown, Grand Cayman   
                                   Cayman Islands, British West Indies

Officers:

     Kevin Bromley                 Vice President, Treasurer, and 
                                   Assistant Secretary 
                                   MeesPierson (Cayman) Limited
                                   British American Centre  
                                   Dr. Roy's Drive- Phase 3   
                                   Georgetown, Grand Cayman    
                                   Cayman Islands, British West Indies

     Sandra Wight                  Secretary and Assistant Treasurer
                                   Assistant Secretary
                                   MeesPierson (Cayman) Limited
                                   British American Centre  
                                   Dr. Roy's Drive- Phase 3   
                                   Georgetown, Grand Cayman    
                                   Cayman Islands, British West Indies


Gabelli Asset Management Company 
International Advisory Services Ltd.

Directors:

     Marc J. Gabelli               See above-Gabelli Funds, Inc.

     Stephen G. Bondi              See Above-Gabelli Funds, Inc.

     Joseph R. Rindler, Jr.        See above-GAMCO Investors, Inc.

     Michael J. Burns              Appleby, Spurling & Kempe
                                   Cedar House
                                   41 Cedar Avenue
                                   Hamilton, HM12
                                   Bermuda             



     Douglas Molyneux              Appleby, Spurling & Kempe
                                   Cedar House
                                   41 Cedar Avenue
                                   Hamilton, HM12
                                   Bermuda        


Lynch Corporation
8 Sound Shore Drive
Greenwich, CT  06830

Directors:

     Paul J. Evanson               President               
                                   Florida Light & Power Co.
                                   P.O Box 14000
                                   700 Universe Blvd.
                                   Juno Beach, Fl 33408

     Morris Berkowitz              Business Consultant
                                   163-43 Willets Point Blvd.
                                   Whitestone, NY 11357

     Mario J. Gabelli              See above-Gabelli Funds, Inc.

     Paul Woolard                  Business Consultant
                                   116 East 68th Street
                                   New York, NY 10021

     E. Val Cerutti                Business Consultant          
                                   Cerutti Consultants 
                                   227 McLain Street
                                   Mount Kisco, NY   10549

     Ralph R. Papitto              Chairman of the Board
                                   AFC Cable Systems, Inc.
                                   50 Kennedy Plaza
                                   Suite 1250
                                   Providence, RI  02903

     Salvatore Muoio               S. Muoio & Co., LLC
                                   655 Third Avenue
                                   New York, NY 10017       

     John C. Ferrara               110 Edward Place
                                   Stamford, CT  06905

Officers:

     Mario J. Gabelli              Chairman and Chief Executive Officer

     Joseph H. Epel                Treasurer

     Robert E. Dolan               Chief Financial Officer 

     Carmine Ceraolo               Assistant Controller


     Robert A. Hurwich             Vice President-Administration,
                                   Secretary and General Counsel


Spinnaker Industries, Inc.
600 N. Pearl Street 
Suite 2160
Dallas, TX  75201

Directors:

     Joseph P. Rhein               5003 Central Avenue     
                                   Ocean City, NJ  08226
                                   
     Richard J. Boyle              The Boyle Group, Inc.             
                                   6110 Blue Circle Drive
                                   Suite 250           
                                   Minnetonka, MN  55343

     Ned N. Fleming, III           Boyle, Fleming, 
                                   George & Co., Inc.            
                                   600 N. Pearl Street
                                   Suite 2160
                                   Dallas, TX  75201


     Robert E. Dolan               See above Lynch Corporation

     Anthonie C. van Ekris         Chairman and Chief 
                                   Executive Officer
                                   Balmac International, Inc.
                                   61 Broadway
                                   Suite 1900
                                   New York, NY  10006
Officers:

     James W. Toman                Controller          

     Ned N. Fleming, III           President

     Richard J. Boyle              Chairman and
                                   Chief Executive Officer

     Robert A. Hurwich             Secretary

     Mark A. Matteson              Vice President, Corporate
                                   Development











Entoleter, Inc.
251 Welton Street
Hamden, CT  06517

Directors:

     Ned N. Fleming, III           See above-Spinnaker

     Mark A. Matteson              See above-Spinnaker

     James W. Toman                See above-Spinnaker

     Robert P. Wentzel             See above Entoleter

     James Fleming                 230 Saugatuck Avenue, Unit 8
                                   Westport, CT  06880

Officers:

     James W. Toman                Chief Financial Officer
                                   and Secretary

     Robert P. Wentzel             President

     Anthony R. Massaro            Vice President-Manufacturing


Western New Mexico Telephone Company
314 Yankee Street
Silver City, NM  88062

Directors:

     Jack C. Keen                  Chairman

     Jack W. Keen                  President

     Dr. Brian E. Gordon           Vice President

     Mary Beth Baxter              Secretary & Treasurer

     Robert E. Dolan               See above-Lynch Corporation

     Robert A. Hurwich             See above-Lynch Corporation

     Carmine Ceraolo               See above-Lynch Corporation

Officers:

     Jack C. Keen                  Chairman of the Board

     Jack W. Keen                  President

     Jack L. Bentley               Executive Vice President

     Dr. Brian E. Gordon           Vice President

     Charles M. Baxter             Sr. Vice President-Operations
     
     Mary Beth Baxter              Secretary & Treasurer

     Robert A. Hurwich             Assistant Treasurer


Inter-Community Telephone Company
P.O. Box A
Nome, ND  58062

Directors:

     Mary J. Carroll               See above-Lynch Corporation

     Carmine P. Ceraolo            See above-Lynch Corporation
                                   
     Robert E. Dolan               See above-Lynch Corporation

     Joseph H. Epel                See above-Lynch Corporation

     Robert A. Hurwich             See above-Lynch Corporation

     Leone A. Nilsen               President

     Roger J. Nilsen               P.O. Box 146
                                   Hannaford, ND 58448

     Duane A. Plecity              Secretary

     Harry B. Snyder               P.O. Box 131
                                   Buffalo, ND  58011
                                   
     Robert Snyder                 200 Broadway South
                                   Buffalo, ND  58011

Officers:

     Leone A. Nilsen               President
     
     Robert Snyder                 Vice President 
     
     Duane A. Plecity              Secretary
     
     Harry B. Snyder               Treasurer

     Joseph H. Epel                Assistant Treasurer

     Robert A. Hurwich             Assistant Secretary










Lynch Telecommunications Corporation
8 Sound Shore Drive
Greenwich, CT  06830

Directors:

     Richard A. Kiesling           2801 International Lane
                                   Suite 207
                                   Madison, WI  53740           

     Jack C. Keen                  See above-Western New Mexico
                                   Telephone Company

     Robert A. Snyder              See above-Inter-Community
                                   Telephone Company

Officers:

     Robert A. Hurwich             Secretary

     Mary Beth Baxter              Treasurer and 
                                   Assistant Secretary

     Robert E. Dolan               Controller


Lynch Telephone Corporation
8 Sound Shore Drive
Greenwich, CT  06830

Directors:

     Robert E. Dolan               Controller

     Jack C. Keen                  Chairman

Officers:

     Jack C. Keen                  Chairman

     Jack W. Keen                  President

     Robert A. Hurwich             Secretary

     Mary Beth Baxter              Treasurer and 
                                   Assistant Secretary

     Robert E. Dolan               Controller

SCHEDULE II
INFORMATION WITH RESPECT TO
TRANSACTIONS EFFECTED DURING THE PAST SIXTY DAYS OR
SINCE THE MOST RECENT FILING ON SCHEDULE 13D (1)

                                                                                
                                             SHARES PURCHASED        AVERAGE    
                                  DATE            SOLD(-)             PRICE(2)  
                                                                                
COMMON STOCK-IDEX CORP

          GABELLI FUNDS, INC.                                                   
               THE GABELLI EQUITY TRUST,INC.                                    
                                 6/17/97            1,200-           30.9490    
                                 6/09/97            5,000-           30.0740    
                                 6/05/97            3,000-           30.3240    
                                 6/04/97            5,000-           30.0740    
                                 6/03/97            5,000-           29.6990    
               THE GABELLI ASSET FUND                                           
                                 6/16/97            3,000-           30.7407    
                                 6/03/97            5,000-           29.3690    
                                 5/05/97           10,000-           27.8366    
          GAMCO INVESTORS, INC.                                                 
                                 5/29/97            2,000            28.7500    
                                 5/23/97            1,000            28.3750    
          GAMCO INVESTORS, INC.                                                 
                                 6/24/97            5,000-           30.5250    
                                 6/24/97            1,750-           30.5357    
                                 6/23/97            7,400-           30.5591    
                                 6/20/97            4,500-             *DO      
                                 6/20/97              875            31.0000    
                                 6/20/97            2,700-           30.9537    
                                 6/19/97            5,300-           31.2642    
                                 6/18/97            1,250-           30.0000    
                                 6/18/97            1,000-             *DO      
                                 6/12/97              800            29.5000    
                                 6/11/97              700-           29.6250    
                                 6/10/97              800-           29.6250    
                                 6/04/97              750-           28.7252    
                                 6/04/97              750            28.7252    
                                 6/04/97            8,000-           30.0000    
                                 6/02/97              875-           29.1250    
                                 6/02/97            8,225-           29.1258    
                                 5/30/97           22,500-             *DO      
                                 5/29/97            1,500            29.5000    
                                 5/29/97            1,500            28.7500    
                                 5/29/97            8,000-           29.1250    
                                 5/29/97              200            28.6250    
                                 5/27/97            7,550            28.7252    
                                 5/23/97            2,500            28.3750    
                                 5/22/97           46,064-             *DO      
                                 5/05/97            3,000-           27.8750    
                                 5/05/97              250-           27.3750    
                                 5/02/97           12,700-           27.4705    
SCHEDULE II
INFORMATION WITH RESPECT TO
TRANSACTIONS EFFECTED DURING THE PAST SIXTY DAYS OR
SINCE THE MOST RECENT FILING ON SCHEDULE 13D (1)
                                                                                
                                             SHARES PURCHASED        AVERAGE    
                                  DATE            SOLD(-)             PRICE(2)  
                                                                               
COMMON STOCK-IDEX CORP
                                                                                
         GAMCO INVESTORS, INC.                                                 
                                5/02/97            1,500-           27.3750    
                                5/01/97            3,300-           26.4050    
                                5/01/97           13,875-           26.2500    
                                4/30/97              936-           25.8750    
                                4/30/97            4,625-           26.2500    
                                4/30/97            4,625            26.2500    
                                4/25/97            4,500-           25.7500    
                                4/24/97            3,000-           25.6250    
                      
















                                                         





                                                                               
(1) UNLESS OTHERWISE INDICATED, ALL TRANSACTIONS WERE EFFECTED        
    ON THE NY STOCK EXCHANGE.                                         

(2) PRICE EXCLUDES COMMISSION.                                        

(*) RESULTS IN CHANGE OF DISPOSITIVE POWER AND BENEFICIAL OWNERSHIP.