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                                                                     EXHIBIT 3.4

                                                                 PAGE 1

                                STATE OF DELAWARE
                        OFFICE OF THE SECRETARY OF STATE
                      ------------------------------------


         I, EDWARD J. FREEL, SECRETARY OF STATE OF THE STATE OF DELAWARE, DO
HEREBY CERTIFY THE ATTACHED IS A TRUE AND CORRECT COPY OF THE CERTIFICATE OF
OWNERSHIP, WHICH MERGES:

         "APACHE PHN COMPANY, INC.", A DELAWARE CORPORATION,

         WITH AND INTO "APACHE CORPORATION" UNDER THE NAME OF" APACHE
CORPORATION", A CORPORATION ORGANIZED AND EXISTING UNDER THE LAWS OF THE STATE
OF DELAWARE, AS RECEIVED AND FILED IN THIS OFFICE THE FIRST DAY OF JULY, A.D.
1998, AT 4:30 O'CLOCK P.M.

         A FILED COPY OF THIS CERTIFICATE HAS BEEN FORWARDED TO THE NEW CASTLE
COUNTY RECORDER OF DEEDS.


                                          /s/ Edward J. Freel
                                          -----------------------------------
                                          Edward J. Freel, Secretary of State

                                     [SEAL]


0482215 8100M                             AUTHENTICATION:        9175881
981258093                                           DATE:        07-02-98


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                       CERTIFICATE OF OWNERSHIP AND MERGER
                                     MERGING
                            APACHE PHN COMPANY, INC.
                                      INTO
                               APACHE CORPORATION


         Apache Corporation, a corporation organized and existing under the laws
of the State of Delaware, DOES HEREBY CERTIFY:

         FIRST: That Apache Corporation was incorporated on the 6th day of
December, 1954, pursuant to the General Corporation Law of the State of
Delaware.

         SECOND: That Apache Corporation owns all of the issued and outstanding
shares of the capital stock of Apache PHN Company, Inc., a corporation which was
incorporated on the 19th day of May, 1930, pursuant to the General Corporation
Law of the State of Delaware.

         THIRD: That Apache Corporation, by the following resolutions of its
Board of Directors, duly adopted by unanimous written consent dated June 29,
1998, determined to and did merge into itself said Apache PHN Company, Inc.:

                  RESOLVED that Apache PHN Company, Inc. ("Apache PHN"), a
         wholly owned subsidiary of Apache Corporation, be merged with and into
         Apache Corporation ("Apache"), with Apache being the surviving
         corporation.

                  FURTHER RESOLVED that the merger shall be effective as of July
         1, 1998.

                  FURTHER RESOLVED that all of the shares of the capital stock
         of Apache PHN issued and outstanding as of the effective date of the
         merger shall be cancelled without consideration.

                  FURTHER RESOLVED that upon the merger taking effect, Apache
         shall thereupon and thereafter possess all the rights, privileges,
         immunities, and franchises, of a public as well as a private nature, of
         each of Apache and Apache PHN; that all property, real, personal, and
         mixed, and all debts due on whatever account, including subscriptions
         to shares, and all other chooses in action, and every other interest of
         or belonging to or due to Apache PHN shall be deemed to be transferred
         to and vested in Apache without further act or deed; that the title to
         any real estate, or any interest therein vested in either of Apache or
         Apache PHN shall not revert or be in any way impaired by reason of the
         merger; and that such transfer to and vesting in Apache shall be deemed
         to occur by operation of law, and no consent or approval of any other
         person shall be required in connection with any such transfer or
         vesting unless such consent or approval is specifically required in the
         event of merger by law or by express 



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         provision in any contract, agreement, decree, order, or other
         instrument to which either of Apache or Apache PHN is a party or by
         which either is bound.

                  FURTHER RESOLVED that upon the merger taking effect, Apache
         shall be responsible and liable for all the liabilities and obligations
         of Apache PHN; that any claim existing or action or proceeding, whether
         civil or criminal, pending by or against Apache PHN may be prosecuted
         as if the merger had not taken place; and that neither the rights of
         creditors nor any liens upon the property of either of Apache or Apache
         PHN shall be impaired by such merger.

                  FURTHER RESOLVED that the proper officers of Apache are hereby
         authorized and directed, in the name and on behalf of Apache, to
         prepare and execute a Certificate of Ownership and Merger setting forth
         a copy of the resolutions authorizing the merger of Apache PHN with and
         into Apache and the assumption by Apache of the liabilities and
         obligations of Apache PHN, and the date of adoption thereof, and to
         cause such Certificate of Ownership and Merger to be filed with the
         Delaware Secretary of State and a certified copy of same recorded in
         the office of the Recorder of Deeds of New Castle County.

                  FURTHER RESOLVED that the proper officers of Apache be, and
         they hereby are, authorized and directed to take such further action
         and to execute such certificates and other documents as they, in their
         discretion, shall deem necessary or advisable to consummate the merger
         and effect the foregoing resolutions.

         FOURTH: Anything herein or elsewhere to the contrary notwithstanding,
this merger may be amended or terminated and abandoned by the Board of Directors
of Apache Corporation at any time prior to the date of filing the merger with
the Delaware Secretary of State.

         IN WITNESS WHEREOF, Apache Corporation has caused this Certificate of
Ownership and Merger to be executed by its duly authorized officers as of this
29th day of June, 1998.

                                           APACHE CORPORATION


                                           By:  /s/ G. STEVEN FARRIS
                                                -------------------------------
                                                    G. Steven Farris
                                                    President and Chief 
                                                    Operating Officer

ATTEST:


/s/ CHERI L. PEPER
- ------------------------------------
Cheri L. Peper
Corporate Secretary



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STATE OF TEXAS      )
                    )
COUNTY OF HARRIS    )


         The foregoing instrument was acknowledged before me this 29th day of
June, 1998, on behalf of Apache Corporation, by G. Steven Farris, President and
Chief Operating Officer of Apache Corporation, a Delaware corporation.



[Seal]                                     /s/ SUSAN CHARBA
                                           -----------------------------------
                                           Susan Charba, Notary Public in and
                                           for the State of Texas

                                           My Commission Expires
                                           November 21, 1999



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