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                                                                   EXHIBIT 10.19


                               FIRST AMENDMENT TO
                           FOURTH AMENDED AND RESTATED
                                CREDIT AGREEMENT

          This FIRST AMENDMENT TO FOURTH AMENDED AND RESTATED CREDIT AGREEMENT
("Amendment") is made as of July 7, 1998, by and among COHO RESOURCES, INC., a
Nevada corporation ("CRI"), COHO LOUISIANA PRODUCTION COMPANY, a Delaware
corporation (the "Production Company"), COHO EXPLORATION, INC., a Delaware
corporation ("Exploration") COHO OIL & GAS, INC. (formerly named Coho
Acquisition Company), a Delaware corporation ("Oil & Gas"), (CRI, the Production
Company, Exploration and Oil & Gas are sometimes collectively referred to as the
"Borrowers" and individually as a "Borrower"), COHO ENERGY, INC., a Texas
corporation ("Holdings") (the Borrowers and Holdings are sometimes referred to
herein together as the "Companies" or individually as a "Company"), those banks
or other lending institutions which are signatory hereto and which constitute
the Required Lenders as provided in the Original Agreement (as defined below)
(collectively, the "Required Lenders"), PARIBAS, a bank organized under the laws
of the Republic of France acting through its Houston Agency ("PARIBAS") in its
capacity as Administrative Agent for the Lenders (in such capacity, together
with its successors in such capacity, the "Administrative Agent"), and BANK ONE,
N.A., a national banking association (successor by merger to Bank One, Texas,
N.A. and referred to herein as "Bank One"), and MEESPIERSON CAPITAL CORP., a
Delaware corporation ("MeesPierson"), as Co-Documentation Agents for the Lenders
(Bank One and MeesPierson in such capacities, together with their successors in
such capacities, the "Co-Documentation Agents").

                                R E C I I A L S

          A. The parties hereto and certain other banks and lending institutions
(the "Other Lenders") entered into that certain FOURTH AMENDED AND RESTATED
CREDIT AGREEMENT dated as of December 18, 1997 (the "Original Agreement")
pursuant to which the Lenders agreed to lend the Borrowers a maximum of Three
Hundred Million Dollars ($300,000,000.00) pursuant to the terms and conditions
thereof.

          B. The Borrowers and its Affiliates which are parties to the Original
Agreement have requested that the Original Agreement be amended and modified in
certain respects as provided herein, which request has been approved by those
Lenders which constitute the Required Lenders.

          NOW, THEREFORE, in consideration of the premises and the mutual
covenants herein contained, the parties hereto agree as follows:

          1. Terms. All capitalized terms used herein and not specifically
defined herein shall have the meanings given them in the Original Agreement.



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          2. Amendment of Section 1,01. Section 1.01 is amended by adding to it
the following definition of "Threshold Amount" and amending the definition of 
"Applicable Margin" as follows:

                       "Threshold Amount" means the Dollar amount of Revolving
             Advances, calculated in accordance with Section 3 of the First
             Amendment to Fourth Amended and Restated Credit Agreement, among
             the Borrowers, the Lenders and others dated July 7, 1998, above
             which the Applicable Margin increases over the Applicable Margin
             which applies to Revolving Advances at or below such Dollar amount,
             all as provided in the last sentence to the definition of
             Applicable Margin.

             The following sentence shall be added to the end of the definition
          of "Applicable Margin":

             "The Applicable Margin for all Revolving Advances outstanding in
             excess of the Threshold Amount shall be (x) with respect to Prime
             Rate Advances, one percent (1.00%) and (y) with respect to
             Eurodollar Advances, two and one-half percent (2.50%)."

          3. Borrowing Base and Threshold Amount. For the period from July 7,
1998 until October 31, 1998, the (a) Borrowing Base shall be Three Hundred
Million Dollars ($300,000,000.00) and (b) the Threshold Amount shall be Two
Hundred Seventy Million Dollars ($270,000,000.00); provided, however, if before
October 31, 1998, a redetermination of the Borrowing Base should be required
pursuant to Section 2.10(e), the Borrowing Base and the Threshold Amount shall
be redetermined by the Supermajority Lenders in accordance the standards set
forth in Section 2.10(f). Such redeterminations shall be effective until October
31, 1998, at which time (x) the applicability of the Threshold Amount shall no
longer apply to the Agreement and (y) all redeterminations of the Borrowing
Base, if any, shall thereafter be made in accordance with Section 2.10 of the
Agreement.

          4. Amendment of Section 7.01(b). Section 7.01(b) of the Original
Agreement is amended by deleting it in its entirety and replacing it with the
following:

          (b) Interest Coverage Ratio. Holdings will maintain a minimum Interest
          Coverage Ratio measured at the end of the following periods in the
          amounts set opposite each such period end:

<TABLE>
<CAPTION>
Periods Ended                               Minimum Interest Coverage Ratio
-------------                               -------------------------------
<S>                                         <C>
June 30, 1998 - March 31, 1999              1.5 to 1.0
June 30, 1999 - September 30, 1999          1.75 to 1.0
December 31, 1999                           2.00 to 1.0
March 31, 2000                              2.25 to 1.0
Quarters ended thereafter                   2.50 to 1.0
</TABLE>


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          5. Threshold Activation Fee. If the Borrowers should request and
receive Revolving Advances above the Threshold Amount, the Borrowers shall
jointly and severally pay to the Administrative Agent, for the benefit of each
Lender, a Threshold activation fee in the amount of one-half of one percent
(.50%) of the Revolving Advances in excess of the Threshold Amount. Such fee
shall be due and payable upon the funding of the amounts in excess of the
Threshold Amount.

          6. Amendment Fee and Expenses. Upon the execution and delivery of this
Amendment, the Borrowers shall pay to the Administrative Agent, for the benefit
of each Lender, an amendment fee in the amount of Fifteen Thousand Dollars
($15,000) per Lender and the costs and expenses (including reasonable attorneys'
fees) incurred by the Administrative Agent in negotiating and documenting this
Amendment.

          7. Miscellaneous.

          7.1 Headings. Section headings are for reference only and shall not
affect the interpretation or meanings of any provision of this Amendment.

          7.2 Effect of this Amendment. The Original Agreement, as amended by
this Amendment, shall remain in full force and effect except that any reference
therein, or in any other Loan Document referring to the Original Agreement,
shall be deemed to refer to the Original Agreement as amended by this Amendment.

          7.3 GOVERNING LAW. THIS AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED
IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK AND APPLICABLE FEDERAL
LAW.

          7.4 Counterparts. This Amendment may be executed by the different
parties hereto on separate counterparts, each of which, when so executed, shall
be deemed an original but all such counterparts shall constitute but one and the
same Amendment.

          7.5 NO ORAL AGREEMENTS. THE ORIGINAL AGREEMENT, AS AMENDED BY THIS
AMENDMENT, TOGETHER WITH THE OTHER LOAN DOCUMENTS, REPRESENTS THE ENTIRE
AGREEMENT AMONG THE PARTIES AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR
CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO
UNWRITTEN ORAL AGREEMENTS BETWEEN OR AMONG THE PARTIES.

          7.6 Representations. The Borrowers hereby represent and warrant (a)
that they have the corporate power and authority to enter into and perform their
obligations under this Agreement, (b) that their execution, delivery and
performance of this Agreement have been duly authorized by all necessary
corporate acts on the part of each, and (c) that no Event of Default or
Potential Default exists.


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          IN WITNESS WHEREOF, the Borrowers, Holdings, the Administrative Agent,
the Co-Documentation Agents and the Lenders have executed this Agreement as of
the date first written above.

                                    BORROWERS:                                  
                                    
                                    COHO RESOURCES, INC.
                                    
                                    
                                    By:  /s/ EDDIE M. LEBLANC, III
                                       ----------------------------------
                                         Eddie M. LeBlanc, III 
                                         Senior Vice President and 
                                         Chief Financial Officer
                                    
                                    
                                    COHO LOUISIANA PRODUCTION COMPANY
                                    
                                    By:  /s/ EDDIE M. LEBLANC, III
                                       ----------------------------------
                                         Eddie M. LeBlanc, III
                                         Senior Vice President and
                                         Chief Financial Officer
                                    
                                    
                                    COHO EXPLORATION, INC.
                                    
                                    By:  /s/ EDDIE M. LEBLANC, III
                                       ----------------------------------
                                         Eddie M. LeBlanc, III
                                         Senior Vice President and
                                         Chief Financial Officer
                                    
                                    
                                    COHO OIL & GAS, INC.
                                    
                                    By:  /s/ EDDIE M. LEBLANC, III
                                       ----------------------------------
                                         Eddie M. LeBlanc, III
                                         Senior Vice President and
                                         Chief Financial Officer
                                    

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