<PAGE>

                                                                  Exhibit (4)(i)

                                                                      Rev. 10/99

     UNLESS THIS SENIOR NOTE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE
DEPOSITORY TRUST COMPANY (55 WATER STREET, NEW YORK, NEW YORK) TO THE BANK OR
ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY SENIOR NOTE
ISSUED UPON REGISTRATION OR TRANSFER OF, OR IN EXCHANGE FOR, OR IN LIEU OF, THIS
SENIOR NOTE IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS
REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY AND
ANY PAYMENT HEREON IS MADE TO CEDE & CO., 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.

     IF THIS SENIOR NOTE IS ISSUED WITH "ORIGINAL ISSUE DISCOUNT" FOR PURPOSES
OF SECTION 1273 OF THE INTERNAL REVENUE CODE OF 1986, AS AMENDED, THE FOLLOWING
SHALL BE COMPLETED:  THE FOLLOWING INFORMATION IS PROVIDED SOLELY FOR PURPOSES
OF APPLYING SECTIONS 1272, 1273 AND 1275 OF THE UNITED STATES INTERNAL REVENUE
CODE OF 1986, AS AMENDED, TO THIS SENIOR NOTE.  THE ISSUE DATE OF THIS SENIOR
NOTE IS _______________.  THE ISSUE PRICE OF THIS SENIOR NOTE IS _____% OF ITS
PRINCIPAL AMOUNT.  THE AMOUNT OF ORIGINAL ISSUE DISCOUNT ON THIS SENIOR NOTE IS
$______________ PER $1,000 OF THE INITIAL PRINCIPAL AMOUNT, THE YIELD TO
MATURITY IS _____%, AND THE AMOUNT OF THE ORIGINAL ISSUE DISCOUNT ALLOCABLE TO
THE INITIAL SHORT ACCRUAL PERIOD, IF ANY, IS $_________ PER $1,000 OF THE
INITIAL PRINCIPAL AMOUNT, DETERMINED ON THE BASIS OF THE EXACT METHOD.

No. SEN FXR-______________                                   REGISTERED
CUSIP NO.: _______________



                          THE NORTHERN TRUST COMPANY

                            GLOBAL SENIOR BANK NOTE
                                 (Fixed Rate)


ORIGINAL ISSUE DATE:                     PRINCIPAL AMOUNT:

INTEREST RATE:  _______%                 MATURITY DATE:

INTEREST PAYMENT                         REGULAR RECORD DATES (If other than
DATES:                                   the April 1 or October 1, prior to
                                         each Interest Payment Date):
<PAGE>

INTEREST PAYMENT                         REGULAR RECORD DATES (If other than
DATES:                                   the April 1 or October 1, prior to

INITIAL REDEMPTION DATE:                 INITIAL REDEMPTION
                                         PERCENTAGE:

ANNUAL REDEMPTION                        HOLDER'S OPTIONAL
PERCENTAGE REDUCTION:                    REPAYMENT DATE(S):

ORIGINAL ISSUE                           OID AMOUNT:
DISCOUNT NOTE:

Yes:_____  No:_____                      DEFAULT RATE: ____ %

OTHER PROVISIONS:

     The Northern Trust Company, an Illinois banking corporation (the "Bank"),
for value received, hereby promises to pay to Cede & Co., or registered assigns,
the principal amount specified on the face hereof in United States Dollars on
the Maturity Date specified above and to pay interest thereon from the Original
Issue Date specified above or from the most recent interest payment date to
which interest on this Senior Note (or any predecessor Senior Note) has been
paid or made available for payment, semi-annually on April 15 and October 15 of
each year (unless otherwise specified on the face hereof) (each, an "Interest
Payment Date") and at maturity or upon earlier redemption or repayment, if
applicable, commencing on the first Interest Payment Date next succeeding the
Original Issue Date (or, if the Original Issue Date is between a Regular Record
Date and the Interest Payment Date immediately following such Regular Record
Date, on the second Interest Payment Date following the Original Issue Date), at
the Interest Rate per annum specified above, until the principal hereof is paid
or made available for payment, and (to the extent that the payment of such
interest shall be legally enforceable) at such Interest Rate (or the Default
Rate per annum specified above) on any overdue principal and premium, if any,
and on any overdue installment of interest.  Notwithstanding the foregoing, if
this Senior Note has a maturity of one year or less, interest will be paid only
at maturity.  The interest so payable, and punctually paid or made available for
payment, on any Interest Payment Date will be paid to the person in whose name
this Senior Note (or any predecessor Senior Note) is registered at the close of
business on the Regular Record Date for such interest, which shall be the

                                      -2-
<PAGE>

April 1 and October 1 (whether or not a Business Day (as defined below)), as the
case may be, next preceding the applicable Interest Payment Date (unless
otherwise specified on the face hereof); provided, however, that interest
payable at maturity or upon earlier redemption or repayment, if applicable, will
be payable to the person to whom principal shall be payable.

     Payment of principal of, and premium, if any, and interest on, this Senior
Note will be made 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.
The Bank will at all times appoint and maintain a paying agent (the "Paying
Agent") authorized by the Bank to pay the principal of, and premium, if any, and
interest on, this Senior Note on behalf of the Bank and having an office or
agency (the "Paying Agent Office") in The City of New York or the City of
Chicago, Illinois (the "Place of Payment"), where this Senior Note may be
presented or surrendered for payment and where notices, designations or requests
in respect of payments with respect to this Senior Note may be served.  The Bank
has initially appointed itself as the Paying Agent, with the Paying Agent Office
currently located at 50 South LaSalle Street (Level BB-A), Chicago, Illinois
60675, Attention: Securities Services.

     THIS SENIOR NOTE IS A DIRECT, UNCONDITIONAL, UNSECURED AND UNSUBORDINATED
GENERAL OBLIGATION OF THE BANK AND DOES NOT EVIDENCE A DEPOSIT INSURED BY THE
FEDERAL DEPOSIT INSURANCE CORPORATION OR ANY OTHER GOVERNMENT AGENCY.  THIS
SENIOR NOTE RANKS PARI PASSU WITH ALL OTHER UNSECURED AND UNSUBORDINATED
OBLIGATIONS OF THE BANK, EXCEPT DEPOSITS AND OTHER OBLIGATIONS THAT ARE SUBJECT
TO A PRIORITY OR PREFERENCE.  UNDER APPLICABLE LAW, CLAIMS OF CERTAIN CREDITORS,
INCLUDING HOLDERS OF DEPOSITS IN THE BANK, WOULD BE ENTITLED TO PRIORITY OVER
CLAIMS OF UNSECURED GENERAL CREDITORS OF THE BANK, INCLUDING THE HOLDER OF THIS
SENIOR NOTE, IN THE EVENT OF A LIQUIDATION OR OTHER RESOLUTION OF THE BANK.

     Payment of the principal of, and premium, if any, and interest on, this
Senior Note due at maturity or upon earlier redemption or repayment, if
applicable, will be made in immediately available funds upon presentation and
surrender of this Senior Note to the Paying Agent at the Paying Agent Office in
the Place of Payment; provided that this Senior Note is presented to the Paying
Agent in time for the Paying Agent to

                                      -3-
<PAGE>

make such payment in accordance with its normal procedures. Payments of interest
on this Senior Note (other than at maturity or upon earlier redemption or
repayment) will be made by wire transfer to such account as has been
appropriately designated to the Paying Agent by the person entitled to such
payments.

     This Senior Note is one of a duly authorized issue of Senior Bank Notes due
from 30 days to fifteen years from date of issue of the Bank (herein called the
"Senior Notes").

     Payments of interest hereon on any Interest Payment Date will include
interest accrued to, but excluding, such Interest Payment Date.  Interest hereon
shall be computed on the basis of a 360-day year of twelve 30-day months,
provided that if this Senior Note has a maturity of one year or less, interest
hereon shall be computed on the basis of actual days divided by 360.

     If any Interest Payment Date, Maturity Date or date of earlier redemption
or repayment of this Senior Note falls on a day which is not a Business Day, the
related payment of principal, premium, if any, or interest shall be made on the
next succeeding Business Day with the same force and effect as if made on the
date such payment were due, and no interest shall accrue on the amount so
payable for the period from and after such Interest Payment Date, Maturity Date
or date of earlier redemption or repayment, as the case may be.  "Business Day"
means any day other than a Saturday, Sunday or a day on which banking
institutions in The City of New York or the City of Chicago, Illinois generally
are authorized or obligated by law or executive order to close.

     This Senior Note will not be subject to any sinking fund.  If so provided
on the face of this Senior Note, this Senior Note may be redeemed by the Bank on
and after the Initial Redemption Date, if any, specified on the face hereof.  If
no Initial Redemption Date is specified on the face hereof, this Senior Note may
not be redeemed prior to the Maturity Date.  On and after the Initial Redemption
Date, if any, this Senior Note may be redeemed at any time either in whole or in
part from time to time in increments of $1,000 (provided that any remaining
principal amount hereof shall be at least $250,000) at the option of the Bank at
the applicable Redemption Price (as defined below), together with accrued and
unpaid interest hereon at the applicable rate borne by this Senior Note to the
date of

                                      -4-
<PAGE>

redemption (each such date, a "Redemption Date"), on written notice given not
more than 60 nor less than 30 calendar days prior to the Redemption Date by the
Bank to the registered holder hereof. Whenever less than all the Senior Notes at
any time outstanding are to be redeemed, the terms of the Senior Notes to be so
redeemed shall be selected by the Bank. If less than all the Senior Notes with
identical terms at any time outstanding are to be redeemed, the Senior Notes to
be so redeemed shall be selected by the Paying Agent by lot or in any usual
manner approved by it. In the event of redemption of this Senior Note in part
only, a new Senior Note for the unredeemed portion hereof shall be issued in the
name of the holder hereof upon the surrender hereof.

     The "Redemption Price" shall initially be the Initial Redemption Percentage
specified on the face hereof of the principal amount of this Senior Note to be
redeemed and shall decline at each anniversary of the Initial Redemption Date
specified on the face hereof by the Annual Redemption Percentage Reduction, if
any, specified on the face hereof, of the principal amount to be redeemed until
the Redemption Price is 100% of such principal amount.

     This Senior Note may be subject to repayment at the option of the holder
hereof in accordance with the terms hereof on the Holder's Optional Repayment
Date(s), if any, specified on the face hereof.  If no Holder's Optional
Repayment Date is specified on the face hereof, this Senior Note will not be so
repayable at the option of the holder hereof prior to maturity.  On any Holder's
Optional Repayment Date, this Senior Note will be repayable in whole or in part
in increments of $1,000 (provided that any remaining principal amount hereof
will be at least $250,000) at the option of the holder hereof at a repayment
price equal to 100% of the principal amount to be repaid, together with accrued
and unpaid interest hereon payable to the date of repayment.  For this Senior
Note to be repaid in whole or in part at the option of the holder hereof on a
Holder's Optional Repayment Date, this Senior Note must be given, with the form
entitled "Option to Elect Repayment" below duly completed, to the Paying Agent
at its offices located at 50 South LaSalle Street (Level BB-A), Chicago,
Illinois  60675,  Attention:  Securities Services, or at such other address
which the Bank shall from time to time notify the holders of the Senior Notes,
not more than 60 nor less than 30 days prior to

                                      -5-
<PAGE>

such Holder's Optional Repayment Date. Exercise of such repayment option by the
holder hereof shall be irrevocable.

     If this Senior Note is an Original Issue Discount Note and if an Event of
Default with respect to the Senior Notes shall have occurred and be continuing,
the Default Amount (as defined hereafter) of this Senior Note may be declared
due and payable in the manner and with the effect provided herein.  The "Default
Amount" shall be equal to the adjusted issue price as of the first day of the
accrual period as determined under Treasury Regulation Section 1.1275-1(b) (or
successor regulation) under the United States Internal Revenue Code of 1986, as
amended, in which the date of acceleration occurs increased by the daily portion
of the original issue discount for each day in such accrual period ending on the
date of acceleration, as determined under Treasury Regulation Section 1.1275-
1(b)(or successor regulation) under the United States Internal Revenue Code of
1986, as amended.  Upon payment of (i) the amount of principal or premium, if
any, so declared due and payable and (ii) interest on any overdue principal and
overdue interest or premium, if any, (in each case to the extent that the
payment of such interest shall be legally enforceable), all of the Bank's
obligations in respect of the payment of the principal of, and interest or
premium, if any, on, this Senior Note shall terminate.

     In case any Senior Note shall at any time become mutilated, destroyed, lost
or stolen and such Senior Note or evidence satisfactory to the Bank of the loss,
theft or destruction thereof (together with indemnity satisfactory to the Bank
and such other documents or proof as may be required in the premises) shall be
delivered to the Bank, a new Senior Note of like tenor will be issued by the
Bank in exchange for the Senior Note so mutilated, or in lieu of the Senior Note
so destroyed or lost or stolen.  All expenses and reasonable charges associated
with procuring the indemnity referred to above and with the preparation,
authentication and delivery of a new Senior Note shall be borne by the holder of
the Senior Note so mutilated, destroyed, lost or stolen.  If any Senior Note
which has matured or is about to mature shall become mutilated, destroyed, lost
or stolen, the Bank may, instead of issuing a substitute Senior Note, pay or
authorize the payment of the same (without surrender thereof except in the case
of a mutilated Senior Note)

                                      -6-
<PAGE>

upon compliance by the holder thereof with the provisions of this paragraph.

     No recourse shall be had for the payment of the principal of, premium, if
any, or interest on, this Senior Note, for any claim based hereon, or otherwise
in respect hereof, against any shareholder, employee, officer or director, as
such, past, present or future, of the Bank or of any successor corporation,
either directly or through the Bank or any successor corporation, whether by
virtue of any constitution, statute or rule of law or by the enforcement of any
assessment or penalty or otherwise, all such liability being, by the acceptance
hereof and part of the consideration for the issue hereof, expressly waived and
released.

     The occurrence of any of the following events shall constitute an "Event of
Default" with respect to this Senior Note: (i) default in the payment of any
interest with respect to this Senior Note when due, which continues for 30 days;
(ii) default in the payment of any principal of, or premium, if any, on, this
Senior Note when due; (iii) the entry by a court having jurisdiction in the
premises of (a) a decree or order for relief in respect of the Bank in an
involuntary case or proceeding under any applicable United States federal or
state bankruptcy, insolvency, reorganization or other similar law or (b) a
decree or order appointing a conservator, receiver, liquidator, assignee,
trustee, sequestrator or any other similar official of the Bank, or of
substantially all of the property of the Bank, or ordering the winding up or
liquidation of the affairs of the Bank, and the continuance of any such decree
or order for relief or any such other decree or order unstayed and in effect for
a period of 60 consecutive days; or (iv) the commencement by the Bank of a
voluntary case or proceeding under any applicable United States federal or state
bankruptcy, insolvency, reorganization or other similar law or of any other case
or proceeding to be adjudicated as bankrupt or insolvent, or the consent by the
Bank to the entry of a decree or order for relief in an involuntary case or
proceeding under any applicable United States federal or state bankruptcy,
insolvency, reorganization or other similar law or to the commencement of any
bankruptcy or insolvency case or proceeding, or the filing by the Bank of a
petition or answer or consent seeking reorganization or relief under any
applicable United States federal or state law, or the consent by the Bank to the
filing of such petition or to the

                                      -7-
<PAGE>

appointment of or taking possession by a custodian, receiver, liquidator,
assignee, trustee, sequestrator or similar official of the Bank or of
substantially all of the property of the Bank, or the making by the Bank of an
assignment for the benefit of creditors, or the taking of corporate action by
the Bank in furtherance of any such action. If an Event of Default shall occur
and be continuing, the holder of this Senior Note may declare the principal
amount of, and accrued interest and premium, if any, on, this Senior Note due
and payable immediately by written notice to the Bank. Upon such declaration and
notice, such principal amount, accrued interest and premium, if any, shall
become due and payable seven calendar days after such notice. Any Event of
Default with respect to this Senior Note may be waived by the holder hereof.

     No provision of this Senior Note shall alter or impair the obligation of
the Bank, which is absolute and unconditional, to pay the principal of, and
premium, if any, and interest on, this Senior Note in U.S. dollars at the times,
places and rate herein prescribed.

     The Bank shall cause to be kept at the corporate trust office of the Senior
Note Registrar designated below a register (the register maintained in such
corporate trust office or any other office or agency of the Bank in the Place of
Payment herein referred to as the "Senior Note Register") in which, subject to
such reasonable regulations as it may prescribe, the Bank shall provide for the
registration of the Senior Notes and of transfers of the Senior Notes.  The Bank
is hereby initially appointed "Senior Note Registrar" for the purpose of
registering the Senior Notes and transfers of the Senior Notes as herein
provided.

     The transfer of this Senior Note is registrable in the Senior Note
Register, upon surrender of this Senior Note for registration of transfer at the
office or agency of the Bank in the Place of Payment, duly endorsed by, or
accompanied by a written instrument of transfer in form satisfactory to the Bank
and the Paying Agent duly executed by, the holder hereof or his attorney duly
authorized in writing, and thereupon one or more new Senior Notes of like tenor,
of authorized denominations and for the same aggregate principal amount, will be
issued to the designated transferee or transferees.  Notwithstanding the
foregoing, the Bank shall not be required to register the

                                      -8-
<PAGE>

transfer of any Senior Note that has been called for redemption during a period
beginning at the opening of business fifteen calendar days before the day of
mailing of a notice of such redemption and ending at the close of business on
the day of such mailing.

     No service charge shall be made for any such registration of transfer or
exchange, but the Bank may require payment of a sum sufficient to cover any tax
or other governmental charge payable in connection therewith.

     The Senior Notes are issuable only in registered form without coupons in
minimum denominations of $250,000 and any integral multiple of $1,000 in excess
thereof.  Each owner of a beneficial interest in this Senior Note is required to
hold a beneficial interest in $250,000 principal amount or any integral multiple
of $1,000 in excess thereof of this Senior Note at all times.

     Prior to due presentment of this Senior Note for registration of transfer,
the Bank, the Paying Agent or any agent of the Bank or the Paying Agent may
treat the person in whose name this Senior Note is registered as the owner
hereof for all purposes, whether or not this Senior Note be overdue, and neither
the Bank, the Paying Agent nor any such agent shall be affected by notice to the
contrary.

     All notices to the Bank under this Senior Note shall be in writing and
addressed to the Bank at 50 South LaSalle Street (Level BB-A), Chicago, Illinois
60675, Attention: Securities Services, or to such other address of the Bank as
the Bank may notify the holders of the Senior Notes.

     This Senior Note shall be governed by, and construed in accordance with,
the laws of the State of Illinois.

                                      -9-
<PAGE>

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


                                               THE NORTHERN TRUST COMPANY



                                               By:____________________________

                                                     Authorized Signatory

                                      -10-
<PAGE>

                                 ABBREVIATIONS


     The following abbreviations, when used in the inscription on the face of
the within Senior Note, shall be construed as though they were written out in
full according to applicable laws or regulations.


            TEN COM   -   as tenants in common

            TEN ENT   -   as tenants by the entireties

            JT TEN    -   as joint tenants with right of survivorship and not as
                          tenants in common


UNIF GIFT MIN ACT - _______________ Custodian ______________
                         (Cust)               (Minor)

           under Uniform Gifts to Minors Act


              __________________________
                       (State)

Additional abbreviations may also be used
though not in the above list.

                                      -11-
<PAGE>

                                   ASSIGNMENT


     FOR VALUE RECEIVED, the undersigned hereby sell(s), assign(s) and
transfer(s) unto _______________________________________________________________

________________________________________________________________________________


PLEASE INSERT SOCIAL SECURITY NUMBER OR OTHER IDENTIFYING NUMBER OF ASSIGNEE

                        _______________________________________

                        _______________________________________


________________________________________________________________________________

________________________________________________________________________________
                  (Please print or typewrite name and address,
                    including postal zip code, of assignee)
________________________________________________________________________________
the within Senior Note and all rights thereunder, and hereby irrevocably
constitutes and appoints _______________________________________________________

________________________________________________________________________________

________________________________________________________________________________

to transfer said Senior Note on the books of the Bank, with full power of
substitution in the premises.

Dated:_______________


                             ___________________________________________________
                             Notice: The signature to this assignment must
                             correspond with the name as written upon the face
                             of the within Senior Note in every particular,
                             without alteration or enlargement or any change
                             whatsoever.

                                      -12-
<PAGE>

                           OPTION TO ELECT REPAYMENT

     The undersigned hereby irrevocably request(s) and instruct(s) the Bank to
repay this Senior Note (or portion hereof specified below) pursuant to its terms
and at a price equal to 100% of the principal amount hereof to be repaid,
together with accrued and unpaid interest hereon, payable to the date of
repayment, to the undersigned, at ______________________________________________

________________________________________________________________________________
 (Please print or typewrite name and address of the undersigned)

     For this Senior Note to be repaid, the undersigned must give to the Paying
Agent at its offices located at 50 South LaSalle Street (Level BB-A), Chicago,
Illinois 60675, Attention: Securities Services, or at such other place or places
of which the Bank shall from time to time notify the holders of the Senior
Notes, not more than 60 days nor less than 30 days prior to the date of
repayment, this Senior Note with this "Option to Elect Repayment" form duly
completed.

     If less than the entire principal amount of this Senior Note is to be
repaid, specify the portion hereof (which shall be increments of $1,000) which
the holder elects to have repaid and specify the denomination or denominations
(which shall be $250,000 or an integral multiple of $1,000 in excess thereof) of
the Senior Notes to be issued to the holder for the portion of this Senior Note
not being repaid (in the absence of any such specification, one such Senior Note
will be issued for the portion not being repaid):

$__________________

Dated:_____________               ________________________________________
                                  NOTICE: The signature on this "Option to Elect
                                  Repayment" form must correspond with the name
                                  as written upon the face of the within Senior
                                  Note in every particular, without alteration
                                  or enlargement or any change whatsoever.

                                      -13-