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                                                                     EXHIBIT 4.1

      THIS SECURITY IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE
HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF A DEPOSITORY OR A
NOMINEE THEREOF. THIS SECURITY MAY NOT BE EXCHANGED IN WHOLE OR IN PART FOR A
SECURITY REGISTERED, AND NO TRANSFER OF THIS SECURITY IN WHOLE OR IN PART MAY BE
REGISTERED, IN THE NAME OF ANY PERSON OTHER THAN SUCH DEPOSITORY OR ITS NOMINEE
EXCEPT IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE.

      UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF
THE DEPOSITORY TRUST COMPANY (55 WATER STREET, NEW YORK, NEW YORK) TO THE ISSUER
OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND SUCH
CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO., OR SUCH OTHER NAME
AS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY, ANY TRANSFER,
PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS
WRONGFUL, SINCE THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

                            ATMOS ENERGY CORPORATION

                       Floating Rate Senior Notes due 2007

No. 1                                                      CUSIP NO. 049560 AD 7

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      Atmos Energy Corporation, a Texas and Virginia corporation (herein called
the "Company", which term includes any successor entity under the Indenture,
hereinafter defined), for value received, hereby promises to pay to Cede & Co.
or registered assigns the principal sum of THREE HUNDRED MILLION DOLLARS
($300,000,000) on October 15, 2007 (the "Maturity Date"), at the office or
agency of the Company referred to below, and to pay interest thereon from
October 22, 2004, or from the most recent Interest Payment Date to which
interest has been paid or duly provided for, quarterly on January 15, April 15,
July 15 and October 15 in each year (each, an "Interest Payment Date"),
commencing January 15, 2005 at the Three-Month LIBOR Rate plus 0.375%, as
determined by the Calculation Agent in accordance with the next succeeding
paragraph, until the principal hereof is paid or duly provided for. The
Three-Month LIBOR Rate will be reset quarterly on each Interest Payment Date
(each of these such dates is referred to as an "Interest Reset Date"), beginning
on January 15, 2005. The interest rate for the first Interest Period shall be
2.465%. Interest payable on each Interest Payment Date will include interest
accrued from and including October 22, 2004, or from and including the most
recent Interest Payment Date to which interest has been paid or duly provided
for, as the case may be, to but excluding such Interest Payment Date.

      Interest will be computed on the basis of a 360-day year and the actual
number of days in an Interest Period. All percentages resulting from any
calculation of the interest rate with respect to these Securities will be
rounded, if necessary, to the nearest one-hundred thousandth of a percentage
point, with five one-millionths of a percentage point rounded upwards (for
example, 9.876545% (or .09876545) being rounded to 9.87655% (or .0987655) and
9.876544% (or .09876544) being rounded to 9.87654% (or .0987654)), and all
dollar amounts in or resulting from any such calculation will be rounded to the
nearest cent (with one-half cent being rounded upwards). The interest rate for
these Securities will in no event be higher than the maximum rate permitted by
New York law as the same may be modified by United States law of general
application.

      Promptly upon determination, the Calculation Agent shall inform the
Trustee and the Company of the interest rate for the next Interest Period. The
Calculation Agent will, upon the request of any Holder of these Securities,
provide the interest rate then in effect, and, if determined, the interest rate
with regards to such Security which will become effective with respect to the
next Interest Period. All calculations made by the Calculation Agent in the
absence of manifest error shall be conclusive for all purposes and binding on
the Company and the Holders of these Securities.

      "Three-Month LIBOR Rate" means the rate for deposits in U.S. dollars for
the three-month period commencing on the applicable Interest Reset Date which
appears on Telerate Page 3750 at approximately 11:00 a.m., London time, on the
second London Banking Day prior to the applicable Interest Reset Date. If this
rate does not appear on Telerate Page 3750, the Calculation Agent will determine
the rate on the basis of the rates at which deposits in U.S. dollars are offered
by four major banks in the London interbank market (selected by the Calculation
Agent) at approximately 11:00 a.m., London time, on the second London Banking
Day prior to the applicable Interest Reset Date to prime banks in the London
interbank market for a period of three months commencing on that Interest Reset
Date and in a principal amount equal to an amount not less than $1,000,000 that
is representative for a single transaction in such market at such time. In such
case, the Calculation Agent will request the principal London office

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of each of the aforesaid major banks to provide a quotation of such rate. If at
least two such quotations are provided, the rate for that Interest Reset Date
will be the arithmetic mean of the quotations, and, if fewer than two quotations
are provided as requested, the rate for that Interest Reset Date will be the
arithmetic mean of the rates quoted by major banks in New York City, selected by
the Calculation Agent, at approximately 11:00 a.m., New York City time, on the
second London Banking Day prior to the applicable Interest Reset Date for loans
in U.S. dollars to leading European banks for a period of three months
commencing on that Interest Reset Date and in a principal amount equal to an
amount not less than $1,000,000 that is representative for a single transaction
in such market at such time. "London Banking Day" means any business day in
which dealings in U.S. dollars are transacted in the London interbank market.

      "Telerate Page 3750" means the display page so designated on the Moneyline
Telerate, Inc. (or such other page as may replace such page on that service or
any successor service for the purpose of displaying London interbank offered
rates of major banks).

      "Calculation Agent" is SunTrust Bank until such time as the Company
appoints a successor calculation agent.

      "Interest Period" means the period commencing on and including the
Interest Payment Date and ending on and including the day immediately preceding
the next succeeding Interest Payment Date with the exception that the first
Interest Period shall commence on October 22, 2004 and end on January 14, 2005.

      Any payment of principal or interest required to be made on a day that is
not a Business Day need not be made on such day, but may be made on the next
succeeding Business Day with the same force and effect as if made on such day
and no interest shall accrue as a result of such delayed payment.

      The interest so payable, and punctually paid or duly provided for, on any
Interest Payment Date will, as provided in the Indenture, be paid to the person
(the "Holder") in whose name this Security (or one or more Predecessor
Securities) is registered at the close of business on the January 1, April 1,
July 1 or October 1 (whether or not a Business Day) next preceding such Interest
Payment Date (a "Regular Record Date"). Any such interest not so punctually paid
or duly provided for ("Defaulted Interest") will forthwith cease to be payable
to the Holder on such Regular Record Date and either may be paid to the Person
in whose name this Security (or one or more Predecessor Securities) is
registered at the close of business on a special record date (the "Special
Record Date") for the payment of such Defaulted Interest to be fixed by the
Trustee (referred to herein), notice whereof shall be given to the Holder of
this Security not less than ten days prior to such Special Record Date, or may
be paid at any time in any other lawful manner, all as more fully provided in
the Indenture.

      For purposes of this Security, "Business Day" means any day that, in the
city of the principal Corporate Trust Office of the Trustee and in the City of
New York, is neither a Saturday, Sunday, or legal holiday nor a day on which
banking institutions are authorized or required by law or regulation to close.

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      Payment of the principal of (and premium, if any) and interest on this
Security will be made at the office or agency of the Company maintained for that
purpose in the Borough of Manhattan, the City of New York, or at such other
office or agency of the Company as may be maintained for such purpose, in such
coin or currency of the United States of America as at the time of payment is
legal tender for payment of public and private debts. So long as this Security
remains in book-entry form, all payments of principal and interest will be made
by the Company in immediately available funds.

      Unless the certificate of authentication hereon has been duly executed by
the Trustee by manual signature, this Security shall not be entitled to any
benefit under the Indenture, or be valid or obligatory for any purpose.

      This Security is one of a duly authorized series of securities of the
Company, designated as the Floating Rate Senior Notes due 2007 (the
"Securities"), issued under an Indenture dated as of May 22, 2001, as it may be
supplemented from time to time (referred to herein as the "Indenture"), between
the Company and SunTrust Bank, as trustee (referred to herein as the "Trustee",
which term includes any successor trustee under the Indenture with respect to
the series of which this Security is a part). A reference is hereby made to the
Indenture for a statement of the respective rights, limitations of rights,
duties, obligations and immunities thereunder of the Company, the Trustee and
the Holders of the Securities, and of the terms upon which the Securities are,
and are to be, authenticated and delivered, except as otherwise provided herein.

      The Securities are initially limited to $300,000,000 aggregate principal
amount. The Company may, at any time, without the consent of the Holders of the
Securities, create and issue additional securities having the same ranking,
interest rate, maturity and other terms as the Securities. Any such additional
securities shall be consolidated and form the same series of the Securities
having the same terms as to status, redemption and otherwise as the Securities
under the Indenture.

      Events of Default. If an Event of Default shall occur and be continuing,
the principal of all the Securities may be declared due and payable in the
manner and with the effect provided in the Indenture.

      Optional Redemption. The Securities will be redeemable, in whole or in
part, at the Company's option, on any Interest Payment Date, on or after April
15, 2006, at a redemption price equal to 100% of the principal amount of the
Securities to be redeemed plus accrued and unpaid interest on the principal
amount of Securities being redeemed to the Redemption Date.

      In the event that less than all of the Securities are to be redeemed at
any time, selection of such Securities for redemption will be made by The
Depository Trust Company ("DTC") during any period the Securities are issued in
the form of a global security registered in the name of DTC or a nominee
thereof; provided that during any period the Securities are issued in
certificated form, the selection of such Securities for redemption will be made
by the Trustee by lot or by such other method as the Trustee in its sole
discretion shall deem fair and appropriate. In no event shall Securities of a
principal amount of $1,000 or less be redeemed in part. Notice of redemption
shall be given by first-class mail, postage prepaid, mailed not less

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than 30 nor more than 60 days before the Redemption Date, to each Holder of
Securities to be redeemed, at its address as shown in the Security Register. If
the Securities are to be redeemed in part only, the notice of redemption that
relates to such Securities shall state the portion of the principal amount
thereof to be redeemed. A new Security in a principal amount equal to the
unredeemed portion thereof will be issued in the name of the Holder thereof upon
surrender for cancellation of the original Security. On and after the Redemption
Date, interest will cease to accrue on Securities or portions thereof called for
redemption unless the Company defaults in the payment of the Redemption Price.

      Sinking Fund. This Security does not have the benefit of any sinking fund
obligations.

      Modification and Waivers; Obligations of the Company Absolute. The
Indenture permits, with certain exceptions as therein provided, the amendment
thereof and the modification of the rights and obligations of the Company and
the rights of the Holders of the Securities. Certain limited amendments may be
effected under the Indenture at any time by the Company and the Trustee without
the consent of any Holders of the Securities. Certain other amendments affecting
the Securities may only be effected under the Indenture with the consent of the
Holders of not less than a majority in aggregate principal amount of the
Securities at the time Outstanding. The Indenture also contains provisions
permitting the Holders of not less than a majority in principal amount of the
Securities at the time Outstanding, on behalf of the Holders of all Outstanding
Securities, to waive compliance by the Company with certain provisions of the
Indenture affecting the Securities. Furthermore, provisions in the Indenture
permit the Holders of not less than a majority in principal amount of the
Outstanding Securities to waive on behalf of all of the Holders of all
Outstanding Securities certain past defaults under the Indenture in respect of
the Securities and their consequences. Any such consent or waiver by or on
behalf of the Holder of this Security shall be conclusive and binding upon such
Holder and upon all future Holders of this Security and of any Security issued
upon the registration of transfer hereof or in exchange herefor or in lieu
hereof whether or not notation of such consent or waiver is made upon this
Security.

      No reference herein to the Indenture and no provision of this Security or
of the Indenture shall alter or impair the obligation of the Company, which is
absolute and unconditional, to pay the principal of (and premium, if any) and
interest on this Security at the times, place and rate, and in the coin or
currency, herein prescribed.

      Defeasance and Covenant Defeasance. The Indenture contains provisions for
defeasance at any time of (a) the entire indebtedness of the Company represented
by this Security and (b) certain restrictive covenants and the related Defaults
and Events of Default, upon compliance by the Company with certain conditions
set forth therein, which provisions apply to this Security.

      Authorized Denominations. The Securities are issuable only in registered
form, without coupons in denominations of $1,000 and any integral multiple
thereof.

      Registration of Transfer or Exchange. As provided in the Indenture and
subject to certain limitations therein set forth, the transfer of this Security
is registrable on the Security

                                       5

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Register of the Company, upon surrender of this Security for registration of
transfer at the office or agency of the Company, duly endorsed by, or
accompanied by a written instrument of transfer in form satisfactory to the
Company and the Security Registrar duly executed by, the Holder hereof or his
attorney duly authorized in writing, and thereupon one or more new Securities,
of authorized denominations and for the same aggregate principal amount, will be
issued to the designated transferee or transferees. At the date of the original
issuance of this Security such office or agency of the Company is maintained by
SunTrust Bank, Corporate Trust Division, 25 Park Place, 24th Floor, Atlanta, GA
30303-2900.

      As provided in the Indenture and subject to certain limitations therein
set forth, the Securities are exchangeable for a like aggregate principal amount
of Securities of a different authorized denomination, as requested by the Holder
surrendering the same.

      No service charge shall be made for any registration of transfer or
exchange or redemption of Securities, but the Company may require payment of a
sum sufficient to pay all documentary, stamp or similar issue or transfer taxes
or other governmental charges payable in connection with any registration of
transfer or exchange.

      Prior to the time of due presentment of this Security for registration of
transfer, the Company, the Trustee and any agent of the Company or the Trustee
may treat the Person in whose name this Security is registered as the owner
hereof for all purposes, whether or not this Security be overdue, and neither
the Company, the Trustee nor any agent shall be affected by notice to the
contrary.

      Modifications to the Indenture pursuant to Section 301 of the Indenture.
The following modifications to the Indenture shall be applicable with respect to
the Securities:

      (a) The defined term "Principal Property" in the Indenture is hereby
deleted in its entirety and replaced by the following:

      "Principal Property" means any natural gas distribution property located
      in the United States, except any such property that in the opinion of the
      Board of Directors of the Company is not of material importance to the
      total business conducted by the Company and its consolidated Subsidiaries.

      (b) The defined term "Restricted Subsidiary" in the Indenture is hereby
deleted in its entirety and replaced by the following:

      "Restricted Subsidiary" means any Subsidiary the amount of Consolidated
      Net Tangible Assets of which constitutes more than 10% of the aggregate
      amount of Consolidated Net Tangible Assets of the Company and its
      Subsidiaries.

      Defined Terms. Subject to the modifications to the Indenture set forth
above, all capitalized terms used in this Security which are defined in the
Indenture shall have the meanings assigned to them in the Indenture.

                                       6

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                  Governing Laws. This Security, the Indenture and the foregoing
modifications to the Indenture shall be governed by and construed in accordance
with the laws of the State of New York, without regard to conflicts of laws
principles that would apply any other law.

                                       7

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                           IN WITNESS WHEREOF, the Company has caused this
instrument to be duly executed.

                                    ATMOS ENERGY CORPORATION

                                    By:
                                        ----------------------------------------
                                        Name:  Louis P. Gregory
                                        Title: Senior Vice President and General
                                               Counsel

Attest:

By:
   ---------------------------
   Name:  Dwala Kuhn
   Title: Corporate Secretary

<PAGE>

                     TRUSTEE'S CERTIFICATE OF AUTHENTICATION

      This is one of the Securities of the series designated therein referred to
in the within-mentioned Indenture.

Dated: October 22, 2004           SUNTRUST BANK,
                                   as Trustee

                                  By:
                                      ------------------
                                      Authorized Officer

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                                 ASSIGNMENT FORM

To assign this Security, fill in the form below:
(I) or (we) assign and transfer this Security to

________________________________________________________________________________
               (Insert assignee's social security or tax I.D. no.)

________________________________________________________________________________

________________________________________________________________________________

________________________________________________________________________________

________________________________________________________________________________
              (Print or type assignee's name, address and zip code)

and irrevocably appoint________________________________________________________
agent to transfer this Security on the books of the Company. The agent may
substitute another to act for him.

Date:___________ Signature: ____________________________________________________
                              (sign exactly as name appears on the other side of
                              this Security)

Signature guaranteed by: ______________________________