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                                                                     Exhibit 4.5


                           (FORM OF FACE OF SECURITY)

         THIS SECURITY IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE
HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF A DEPOSITARY OR A
NOMINEE OF A DEPOSITARY. THIS SECURITY IS EXCHANGEABLE FOR SECURITIES REGISTERED
IN THE NAME OF A PERSON OTHER THAN THE DEPOSITARY OR ITS NOMINEE ONLY IN THE
LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE, AND NO TRANSFER OF THIS
SECURITY (OTHER THAN A TRANSFER OF THIS SECURITY AS A WHOLE BY THE DEPOSITARY TO
A NOMINEE OF THE DEPOSITARY OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY
OR ANOTHER NOMINEE OF THE DEPOSITARY) MAY BE REGISTERED EXCEPT IN LIMITED
CIRCUMSTANCES.

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


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No. __                                                   CUSIP No.  33589B AC 9


                         FIRST PALM BEACH BANCORP, INC.

                    SERIES B 10.35% SENIOR DEBENTURE DUE 2002


         First Palm Beach Bancorp, Inc., a Delaware corporation (the "Company,"
which term includes any successor Person under the Indenture hereinafter
referred to), for value received, hereby promises to pay to ______________ or
registered assigns, the principal sum of $35,000,000 on June 30, 2002 (the
"Maturity Date"), unless previously redeemed, and to pay interest on the
outstanding principal amount hereof from January 31, 1998, or from the most
recent interest payment date (each such date, an "Interest Payment Date") to
which interest has been paid or duly provided for, semi-annually (subject to
deferral as set forth herein) in arrears on June 30 and December 31 of each
year, commencing June 30, 1998, at the rate of 10.35% per annum until the
principal hereof shall have become due and payable, and on any overdue principal
and premium, if any, and (without duplication and to the extent that payment of
such interest is enforceable under applicable law) on any overdue installment of
interest at the same rate per annum compounded semi-annually. The amount of
interest payable on any Interest Payment Date shall be computed on the basis of
a 360-day year of twelve 30-day months and, for any period less than a full
calendar month, the number of days elapsed in such month. In the event that any
date on which the principal of (or premium, if any) or interest on this Security
is payable is not a Business Day, then the payment payable on such date will be
made on the next succeeding day that is a Business Day (and without any interest
or other payment in respect of any such delay), except that if such next
succeeding Business Day falls in the next calendar year, then such payment shall
be made on the immediately preceding Business Day in each case with the same
force and effect as if made on such date.

         The interest installment 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 in whose name this Security (or one or more Predecessor
Securities, as defined in said Indenture) is registered at the close of business
on the regular record date for such interest installment, which shall be the
fifteenth day of the month in which the relevant interest payment date falls.
Any such interest installment not punctually paid or duly provided for shall
forthwith cease to be payable to the holders on such regular record date and 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 to
be fixed by the Trustee for the payment of such defaulted interest, notice
whereof shall be given to the holders of Securities not less than 10 days prior
to such special record date, or may be paid at any time in any other lawful
manner not inconsistent with the requirements of any securities exchange on
which the Securities may be listed, and upon such notice as may be required by
such exchange, all as more fully provided in the Indenture.

         The principal of (and premium, if any) and interest on this Security
shall be payable at the office or agency of the Trustee maintained for that
purpose in any coin or currency of the United States of America that at the time
of payment is legal tender for payment of public and private debts; PROVIDED,
HOWEVER, that, payment of interest may be made at the option of the Company by
(i) check mailed to the holder at such address as shall appear in the Security
Register or (ii) by wire transfer to an account maintained by the Person
entitled thereto, provided that proper written wire transfer instructions have
been received by the relevant record date.

         This Security shall not be entitled to any benefit under the Indenture
hereinafter referred to, be valid or become obligatory for any purpose until the
Certificate of Authentication hereon shall have been signed by or on behalf of
the Trustee.

         The provisions of this Security are continued on the reverse side
hereof and such provisions shall for all purposes have the same effect as though
fully set forth at this place.


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         IN WITNESS WHEREOF, the Company has executed this certificate.

                                        FIRST PALM BEACH BANCORP, INC.

                                        By:       /s/ R. Randy Guemple
                                                 ------------------------------
                                        Name:     R. Randy Guemple
                                        Title:    Executive Vice President and
                                                  Chief Operating Officer and
                                                  Treasurer
                                                

Attest:

By:      /s/ John C. Trammel
         ------------------------------
Name:    John C. Trammel
Title:   Senior Vice President and
         Secretary
        



                          CERTIFICATE OF AUTHENTICATION

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


Dated:   December 23, 1997

                                             THE BANK OF NEW YORK,
                                             as Trustee



                                             By:  /s/ 
                                                 ------------------------------
                                                 Authorized Signatory


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                          (FORM OF REVERSE OF SECURITY)



     This Security is one of the Securities of the Company (herein sometimes
referred to as the "Securities"), specified in the Indenture, all issued or to
be issued under and pursuant to an Indenture, dated as of June 30, 1997 (the
"Indenture"), duly executed and delivered between the Company and The Bank of
New York, as Trustee (the "Trustee"), to which Indenture reference is hereby
made for a description of the rights, limitations of rights, obligations, duties
and immunities thereunder of the Trustee, the Company and the holders of the
Securities.

         In case an Event of Default, as defined in the Indenture, shall have
occurred and be continuing, the principal of all of the Securities (to the
extent such declaration is not automatic upon the occurrence of an Event of
Default as specified in the Indenture) may be declared, and upon such
declaration shall become, due and payable, in the manner, with the effect and
subject to the conditions provided in the Indenture.

         The Indenture contains provisions permitting the Company and the
Trustee, with the consent of the holders of 66-2/3% in aggregate principal
amount of the Securities at the time outstanding, as defined in the Indenture,
to execute supplemental indentures for the purpose of adding any provisions to
or changing in any manner or eliminating any of the provisions of the Indenture
or of modifying in any manner the rights of the holders of the Securities;
provided, however, that no such supplemental indenture shall, without the
consent of each holder of Securities then outstanding and affected thereby, (i)
extend the Maturity Date of any Securities, or reduce the principal amount
thereof, or reduce any amount payable on prepayment thereof, or reduce the rate
or extend the time of payment of interest thereon, or make the principal of, or
interest or premium on, the Securities payable in any coin or currency other
than U.S. dollars, or impair or affect the right of any holder of Securities to
institute suit for the payment thereof, or (ii) reduce the aforesaid percentage
of Securities, the holders of which are required to consent to any such
supplemental indenture. The Indenture also contains provisions permitting the
holders of a majority in aggregate principal amount of the Securities at the
time outstanding affected thereby, on behalf of all of the holders of the
Securities, to waive any past default in the performance of any of the covenants
contained in the Indenture, or established pursuant to the Indenture, and its
consequences, except a default in the payment of the principal of or premium, if
any, or interest on any of the Securities or a default in respect of any
covenant or provision under which the Indenture cannot be modified or amended
without the consent of each holder of Securities then outstanding. Any such
consent or waiver by the holder of this Security (unless revoked as provided in
the Indenture) shall be conclusive and binding upon such holder and upon all
future holders and owners of this Security and of any Security issued in
exchange herefor or in place hereof (whether by registration of transfer or
otherwise), irrespective of whether or not any 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 time and place and at the rate and in the money
herein prescribed.

         The Securities are issuable only in registered form without coupons in
denominations of $100,000 and any integral multiple of $1,000 above $100,000. As
provided in the Indenture and subject to the transfer restrictions limitations
as may be contained herein and therein from time to time, this Security is
transferable by the holder hereof on the Security Register of the Company, upon
surrender of this Security for registration of transfer at the office or agency
of the Company in the City and State of New York accompanied by a written
instrument or instruments of transfer in form satisfactory to the Company or the
Trustee 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 and series will be issued to the
designated transferee or transferees. No service charge will be made for any
such transfer, but the Company may require payment of a sum sufficient to cover
any tax or other governmental charge payable in relation thereto.

         Prior to due presentment for registration of transfer of this Security,
the Company, the Trustee, any authenticating agent, any paying agent, any
transfer agent and the registrar may deem and treat the holder hereof as the
absolute owner hereof (whether or not this Security shall be overdue) for the
purpose of receiving payment of or on account of the principal hereof and
premium, if any, and (subject to the Indenture) interest due hereon and for all
other


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purposes, and neither the Company nor the Trustee nor any authenticating agent
nor any paying agent nor any transfer agent nor any registrar shall be affected
by any notice to the contrary.

         No recourse shall be had for the payment of the principal of or
premium, if any, or interest on this Security, or for any claim based hereon, or
otherwise in respect hereof, or based on or in respect of the Indenture, against
any incorporator, stockholder, officer or director, past, present or future, as
such, of the Company or of any predecessor or successor Person, 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 as part of the consideration for the issuance hereof, expressly
waived and released.

         All terms used in this Security that are defined in the Indenture shall
have the meanings assigned to them in the Indenture.

         THE INDENTURE AND THE SECURITIES SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO CONFLICT OF
LAW PROVISIONS THEREOF.


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                                    EXHIBIT B

                              (FORM OF ASSIGNMENT)

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

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             (Insert assignee's social security or tax I.D. number)

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

and irrevocably appoint ______________________________________________________
to transfer this Note on the books of the Company. The agent may substitute
another to act for him.

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Date: 
      ---------------
                                 Your Signature:  
                                                -------------------------------
                                 (Sign exactly as your name appears on 
                                 the face of this Note)

                                 Signature Guarantee:
                                                      -------------------------