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                                                                     Exhibit 3.1

                            CERTIFICATE OF AMENDMENT
                                       OF
                      RESTATED CERTIFICATE OF INCORPORATION
                                       OF
                                    OMI CORP.

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

                     Pursuant to Section 242 of the General
                    Corporation law of the State of Delaware

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

            OMI Corp., a corporation organized and existing under the General
Corporation Law of the State of Delaware (the "Corporation"), hereby certifies
as follows:

            1. The Restated Certificate of Incorporation of the Corporation was
filed in the office of the Secretary of State of Delaware on December 12, 1983
and amendments to the Certificate of Incorporation were subsequently duly filed
and recorded (the Restated Certificate of Incorporation together with such
amendments shall be hereinafter referred to as the "Restated Certificate of
Incorporation").

            2. The following amendments are to become effective as of June 18,
1998 at 8:00 a.m.

            3. ARTICLE FIRST of the Restated Certificate of Incorporation is
amended to read in full as follows:

            "FIRST: The name of the corporation is Marine Transport
      Corporation."
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            4. The first paragraph of ARTICLE FOURTH of the Restated Certificate
of Incorporation is amended to read in full as follows:

                  FOURTH: The total number of shares of stock which the
      Corporation shall have authority to issue is fifteen million seven hundred
      fifty thousand (15,750,000) of which stock seven hundred fifty thousand
      (750,000) shares of the par value of one dollar ($1.00) each, amounting in
      the aggregate to seven hundred fifty thousand dollars ($750,000), shall be
      Preferred Stock, and of which fifteen million (15,000,000) shares of the
      par value of fifty cents ($.50) each, amounting in the aggregate to seven
      million five hundred thousand dollars ($7,500,000), shall be Common Stock.

            5. Upon the effectiveness of the foregoing amendment to Article
FOURTH of the Restated Certificate of Incorporation, each share of Common Stock
of the Corporation, having a par value of fifty cents ($.50) per share, issued
and outstanding, or held in the treasury of the Corporation, immediately prior
to the effectiveness of such amendment, shall be changed into and become 0.10
fully paid and nonassessable shares of Common Stock having a par value of fifty
cents ($.50) per share. No fractional interests resulting from such conversion
shall be issued, but in lieu thereof, the Corporation will pay cash for each
currently issued and outstanding share of Common Stock, par value one cent
($.0l) per share, representing such fractional interest.

            6. The aforesaid amendments were duly adopted in accordance with the
provisions of Section 242 of the General Corporation Law of the State of
Delaware.


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            IN WITNESS WHEREOF, the Corporation has caused its corporate seal to
be affixed hereto and this certificate to be signed by its President and
attested by its Secretary this 16th day of June, 1998.

                                        OMI CORP.

                                        By: /s/ Craig H. Stevenson
                                            ------------------------------------
                                            Craig H. Stevenson, Jr.
                                            President

[Corporate Seal]

Attest:

By: /s/ Fredric S. London
   ------------------------------------
   Fredric S. London
   Secretary


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