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                                                                  EXHIBIT 3.1(d)



                             ARTICLES SUPPLEMENTARY

                          $0.40 CUMULATIVE CONVERTIBLE
                            PREFERRED STOCK, SERIES D
                        OF CAPSTEAD MORTGAGE CORPORATION

         CAPSTEAD MORTGAGE CORPORATION, a Maryland corporation, having its
principal office in Baltimore City, Maryland (hereinafter called the
"Corporation"), hereby certifies to the State Department of Assessments and
Taxation of Maryland that:

         Pursuant to authority conferred upon the Board of Directors by the
charter, as amended, of the Corporation (the "Charter"), the Board of Directors
on November 30, 1999 adopted a resolution, creating and authorizing the issuance
of a series of 5,378,000 shares of $0.40 Cumulative Convertible Preferred Stock,
Series D, and that the powers, designations, preferences and relative,
participating, optional or other special rights, and the qualifications,
limitations and restrictions thereof, of the shares of such series are as
follows:

         1. Designation and Number of Shares. Five million three hundred
seventy-eight thousand (5,378,000) shares of Preferred Stock of the Corporation,
par value $.10 per share, are hereby designated as the "$0.40 Cumulative
Convertible Preferred Stock, Series D" (hereinafter called the "Series D
Preferred Stock").

         2. Dividends. Holders of shares of Series D Preferred Stock shall be
entitled to receive, when, as and if declared by the Board of Directors, out of
funds of the Corporation legally available for payment thereof, cumulative
preferential cash dividends at the annual rate of forty cents ($0.40) per share
of Series D Preferred Stock (the "Preference Dividend"), payable in equal
quarterly installments of ten cents ($0.10) per share of Series D Preferred
Stock in arrears on the last business day of each calendar quarter (each, a
"Dividend Payment Date"), to holders of record as they appear on the register
for the Series D Preferred Stock of the Corporation on such record dates, not
more than 10 days preceding the payment dates thereof (each, a "Preferred Record
Date"), as may be fixed by the Board of Directors. The amount of any
distribution payable for any distribution period greater or less than a full
calendar quarter shall be prorated and computed on the basis of a 360-day year
of twelve 30-day months. The first Preference Dividend payable per share of
Series D Preferred Stock (the "Initial Dividend") payable on December 31, 1999
shall be an amount calculated as $0.00111 times the number of days having
elapsed from and including the date of issuance of the Series D Preferred Stock
through and including December 30, 1999. Distributions shall accumulate from the
date of original issuance whether or not earned or declared and whether or not
there shall be funds legally available for the payment thereof.

So long as any Series D Preferred Stock shall remain outstanding, no dividend
shall be declared or paid upon or set apart for payment for the Common Stock of
the Corporation, par value $.01 per share (the "Common Stock"), or any other
class or series of stock of the Corporation ranking junior to the Series D


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Preferred Stock in respect of dividends ("Junior Stock"), nor may any Common
Stock or any other Junior Stock be redeemed, purchased or otherwise acquired for
any consideration (or any payment made to or available for a sinking fund for
the redemption of any shares of such stock), unless in each instance full
Preference Dividends on all outstanding shares of Series D Preferred Stock for
all past dividend periods required to be paid shall have been paid at the rate
fixed therefor and the then current quarterly dividend shall have been paid or
declared and sufficient funds set aside for payment thereof. No dividends shall
be declared on any other series or class or classes of stock ranking on a parity
with the Series D Preferred Stock as to dividends (including, without
limitation, outstanding shares of the Corporation's $1.60 Cumulative Preferred
Stock, Series A, the Corporation's $1.26 Cumulative Convertible Preferred Stock,
Series B and the Corporation's $0.56 Cumulative Convertible Preferred Stock,
Series C (collectively, the "Pari Passu Stock")) in respect of any dividend
period thereof unless there shall likewise be or have been declared and
sufficient funds set aside for payment thereof on all shares of Series D
Preferred Stock at the time outstanding dividends for all quarterly periods
coinciding with or ending before the end of such other period, ratably in
proportion to the respective annual dividend rates per annum fixed therefor.
Accumulated and unpaid Preference Dividends required to be paid on any shares of
Series D Preferred Stock shall not bear interest. As used in these Articles
Supplementary, "business day" shall mean a day that is neither a Saturday nor a
Sunday nor a day on which the New York Stock Exchange is closed.

         3. Liquidation. The shares of Series D Preferred Stock shall rank prior
to the shares of Common Stock and any other class of stock of the Corporation
ranking junior to the Series D Preferred Stock upon liquidation, so that in the
event of any liquidation, dissolution or winding up of the Corporation, whether
voluntary or involuntary, the holders of the Series D Preferred Stock shall be
entitled to receive out of the assets of the Corporation available for
distribution to its stockholders, whether from capital, surplus or earnings,
before any distribution is made to holders of shares of Common Stock or any
other such Junior Stock, an amount equal to $4.76 per share (the "Liquidation
Preference") of Series D Preferred Stock plus an amount equal to the Preference
Dividends (whether or not declared) accumulated and unpaid on the shares of
Series D Preferred Stock to the date of final distribution. If upon any
liquidation, dissolution or winding up of the Corporation, the assets of the
Corporation or proceeds thereof, distributable among the holders of shares of
Series D Preferred Stock and holders of any other class or series of stock of
the Corporation ranking on a parity with shares of Series D Preferred Stock as
to payments upon liquidation (including, without limitation, the Pari Passu
Stock), shall be insufficient to pay in full the respective preferential amounts
of shares of Series D Preferred Stock and any other such class or series, then
such assets, or the proceeds thereof, shall be distributed among such holders
ratably in accordance with the respective amounts which would be payable on such
shares if all amounts thereon were paid in full. For the purposes hereof,
neither a consolidation or merger of the Corporation with or into any other
entity, nor a transfer of all or any part of the Corporation's assets for cash,
property or securities shall be considered a liquidation, dissolution or winding
up of the Corporation.

         4. Voting Rights. Without limiting the rights of the holders of the
Series D Preferred Stock to vote separately as a class as provided in Section 5
below, the holders of shares of Series D Preferred Stock shall be entitled to
vote, together as a single group with the holders of the Common Stock and the
holders of any other class or series of stock entitled to vote together with the
holders of the Common Stock, on all matters as to which the holders of the
Common Stock vote. When the Series D Preferred Stock votes together with the
Common Stock and any other such class or series of stock, each share of Series D
Preferred Stock shall entitle its holder to one vote for each share of Common
Stock into which such share of Series D Preferred Stock is convertible
immediately prior to the time of such vote.


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         5. Limitations on Certain Actions. (A) The Corporation shall not,
without the affirmative vote of the holders of a majority of the shares of
Series D Preferred Stock then outstanding, given in person or by proxy at a
meeting called for the purpose of such vote at which the holders of Series D
Preferred Stock shall vote separately as a class, directly or indirectly:

                           (i) create any class or classes of stock ranking
                  prior to Series D Preferred Stock either as to dividends or as
                  to amounts distributable upon liquidation or increase the
                  authorized number of shares of any class or classes of stock
                  ranking prior to Series D Preferred Stock either as to
                  dividends or as to amounts distributable upon liquidation;

                           (ii) authorize any reclassification of Series D
                  Preferred Stock;

                           (iii) amend, alter or repeal any of the provisions of
                  the Charter of the Corporation (including the provisions of
                  this Section 5) so as to affect adversely the preferences,
                  special rights or voting powers of the Series D Preferred
                  Stock; or

                           (iv) merge or consolidate with or into any other
                  entity unless after such transaction the holders of the Series
                  D Preferred Stock either (A) continue to hold such Series D
                  Preferred Stock without any adverse change thereto and there
                  is no class of stock outstanding ranking prior to the Series D
                  Preferred Stock with respect to payment of dividends or upon
                  liquidation or (B) hold a substantially identical security and
                  there is no class of stock outstanding ranking prior to such
                  security with respect to payment of dividends or upon
                  liquidation.

         (B) Except as otherwise provided herein or otherwise required by law,
         no consent of the holders of Series D Preferred Stock shall be required
         for (a) the creation of any indebtedness of any kind of the
         Corporation, (b) the creation, or increase or decrease in the amount,
         of any class or series of stock of the Corporation ranking on a parity
         with the Series D Preferred Stock as to dividends or as to amounts
         distributable upon liquidation, or any other class or series of stock
         of the Corporation not ranking prior to the Series D Preferred Stock as
         to dividends or as to amounts distributable upon liquidation, or (c)
         any increase or decrease in the amount of authorized Common Stock or
         any increase, decrease or change in the par value thereof.

         6. Redemption. Shares of Series D Preferred Stock will be redeemable at
the option of the Corporation by resolution of its Board of Directors, passed by
at least a majority of the members of the Board, at any time after December 9,
2004, in whole or in part, for cash in an amount per share so redeemed equal to
$4.76 per share plus all Preference Dividends on such shares (whether or not
earned or declared) accumulated and unpaid to the date of such redemption (the
"Redemption Price"). If less than all shares of Series D Preferred Stock are to
be redeemed, (i) all arrearages in Preference Dividends on all outstanding
shares of Series D Preferred Stock must be paid in full prior to any such
partial redemption and (ii) the shares of such series to be redeemed shall be
determined by lot or in such other equitable manner as the Board of Directors
may determine.


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         The Corporation shall mail to each record holder of the Series D
Preferred Stock notice of any redemption not less than 30 nor more than 60 days
prior to the date fixed for such Redemption (the "Redemption Date"). Such notice
shall specify the Redemption Date, the place or places where certificates for
shares of Series D Preferred Stock are to be surrendered, the serial number or
numbers of the certificates for shares to be redeemed (if less than all shares
of Series D Preferred Stock are to be redeemed), the Redemption Price, that
shares of Series D Preferred Stock may be convertible into Common Stock at any
time prior to the close of business on the fifth business day preceding the
Redemption Date, and that dividends on Series D Preferred Stock to be redeemed
on the Redemption Date shall cease to accrue on the Redemption Date. Upon
surrender of Series D Preferred Stock in accordance with said notice (properly
endorsed or assigned for transfer if the Corporation shall so require and the
notice shall so state), such Series D Preferred Stock shall be redeemed by the
Corporation at the Redemption Price and in the manner as aforesaid. The
Corporation shall not be required to register a transfer of any shares of Series
D Preferred Stock that have been redeemed after the Redemption Date in respect
thereof.

         If, at any time after the giving of notice of redemption but before the
Redemption Date specified therein, the Corporation shall deposit with a bank or
trust company in the United States, having a capital surplus of at least
$50,000,000, in trust to be applied to the redemption of the shares of Series D
Preferred Stock called for redemption the funds necessary for such redemption,
then from and after the date of such deposit all rights of the holders of the
shares of Series D Preferred Stock so called for redemption shall cease and
terminate, excepting only (i) the right to receive the Redemption Price
therefor, but without interest, and (ii) the right to exercise on or before the
fifth business day preceding the Redemption Date privileges of conversion set
forth in Section 7, and such shares shall not be deemed to be outstanding. Any
funds so deposited which shall not be required for such redemption because of
the exercise of any such right of conversion subsequent to the date of such
deposit shall be returned to the Corporation. In case the holders of shares of
Series D Preferred Stock that shall have been called for redemption shall not,
within five years after the date fixed for redemption, claim the amount
deposited with respect to the redemption thereof, any such bank or trust company
shall, upon demand, pay over to the Corporation such unclaimed amounts and
thereupon such bank or trust company shall be relieved of all responsibility in
respect thereof to such holder and such holder shall look only to the
Corporation for the payment thereof. Any interest accrued on funds so deposited
shall be paid to the Corporation from time to time.

         7. Conversion. The holders of shares of Series D Preferred Stock shall
have conversion rights as follows:

                  (A) The shares of Series D Preferred Stock shall be
         convertible, at the option of the respective holders thereof, at any
         time into fully paid and non-assessable shares of Common Stock of the
         Corporation, at the conversion rate, determined as hereinafter
         provided, in effect at the time of conversion. In case of any call for
         redemption of any shares of Series D Preferred Stock, such right of
         conversion shall terminate, as to any shares designated for redemption,
         at the close of business on the fifth business day preceding the
         Redemption Date unless default is made in the payment of the Redemption
         Price.



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                  (B) Before any holder of Series D Preferred Stock shall be
         entitled to convert the same into shares of Common Stock, such holder
         shall surrender (i) the certificate or certificates therefor, duly
         endorsed or accompanied by proper instruments of transfer, and (ii) if
         such surrender is made after a Preferred Record Date and on or before
         the record date for the payment of quarterly dividends on the Common
         Stock for the quarter in which such Preferred Record Date (or Dates)
         falls (or fall) (any such Preferred Record Date, an "Intervening
         Preferred Date"), a cashier's check or other guaranteed funds in an
         amount equal to the aggregate amount of Preference Dividends declared
         or received on the shares of Series D Preferred Stock on the Dividend
         Payment Date or Dates to which such Intervening Preferred Date or Dates
         related, at the office of the corporation, and shall give written
         notice to the Corporation at such office that such holder elects to
         convert the same. The Corporation, as soon as practicable thereafter,
         shall issue and deliver to such holder, certificates for the number of
         full shares of Common Stock to which such holder shall be entitled as
         aforesaid, together with cash in lieu of any fraction of a share as
         hereinafter provided. Such conversion shall be deemed to have been made
         as of the date of such surrender of the certificate or certificates
         representing the shares of Series D Preferred Stock to be converted
         and, if applicable, the cashier's check or other guaranteed funds, and
         the person or persons entitled to receive the shares of Common Stock
         issuable upon such conversion shall be treated for all purposes as the
         record holder or holders of such shares of Common Stock on said date.

                  (C) Notwithstanding any of the foregoing, all shares of Series
         D Preferred Stock outstanding on December 31, 2005 (the "Conversion
         Date") shall automatically convert into fully paid and non-assessable
         shares of Common Stock, at the conversion rate, determined as
         hereinafter provided, in effect at the time of such conversion;
         provided, however, that if funds are not legally available for the
         payment (in whole or in part) of any accrued but unpaid dividends as of
         the Conversion Date, the amount of such dividends which cannot be
         legally paid by the Corporation as of the Conversion Date ("Unpaid
         Dividends") shall be payable in shares of Common Stock. The number of
         shares of Common Stock to be issued in payment of any Unpaid Dividends
         on each share of Series D Preferred Stock outstanding as of the
         Conversion Date shall be determined by dividing the Unpaid Dividends
         payable on each outstanding share of Series D Preferred Stock by the
         Fair Market Value of a share of Common Stock as of the Conversion Date.
         For purposes of this Section 7(C), "Fair Market Value" shall mean the
         average of the daily closing prices of the Common Stock for the 30
         consecutive business days commencing 45 business days prior to the
         Conversion Date. The Closing price per share of Common Stock for each
         day shall be the last reported sale price regular way, or, in case no
         such reported sale takes place on such day, the average of the reported
         closing bid and asked prices regular way in either case on the New York
         Stock Exchange, or, if the Common Stock is not listed or admitted to
         business on such Exchange, on the principal national securities
         exchange on which the Common Stock is listed or admitted to business,
         or if not listed or admitted to business on any national securities
         exchange, the average of the closing bid and asked prices as furnished
         by the National Quotation Bureau, Incorporated or similar organization
         if the National Quotation Bureau, Incorporated is no longer reporting
         such information. The aggregate number of shares of


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         Common Stock to be issued to each holder of Series D Preferred Stock
         shall be determined and any fractional shares issuable to such holder
         after such aggregation shall be eliminated.

                  (D) The conversion rate shall be one (1) share of Common Stock
         for each share of Series D Preferred Stock converted, such rate being
         subject to adjustment from time to time as follows:

                           (i) If the Corporation shall at any time issue
                  additional shares of Common Stock as a dividend upon any
                  outstanding stock of the Corporation other than the Series D
                  Preferred Stock (which stock is convertible into Common Stock)
                  or subdivide the outstanding shares of Common Stock, or
                  combine the outstanding shares of Common Stock, the conversion
                  rate in effect immediately prior thereto shall be adjusted so
                  that each share of Series D Preferred Stock shall thereafter
                  be convertible into the total number of shares of Common Stock
                  which the holder of a share of Series D Preferred Stock would
                  have held immediately after the happening of any of the
                  aforesaid events had such share been converted immediately
                  prior to the happening of such event. Such adjustment shall
                  become effective immediately after the opening of business on
                  the record date for the determination of stockholders entitled
                  to such dividend, or on the effective date of such subdivision
                  or combination, as the case may be.

                           (ii) If the Corporation shall at any time issue
                  rights or warrants to all holders of its outstanding Common
                  Stock entitling them to subscribe for or purchase shares of
                  Common Stock at a price per share less than the current market
                  price per share of the Common Stock on the record date
                  mentioned below, the conversion rate theretofore in effect
                  immediately prior to such record date shall be adjusted by
                  multiplying such conversion rate by a fraction, of which the
                  numerator shall be the number of shares of Common Stock
                  outstanding on the record date referred to below plus the
                  number of additional shares of Common Stock offered for
                  subscription or purchase, and of which the denominator shall
                  be the number of shares of Common Stock outstanding on such
                  record date plus the number of shares which the aggregate
                  offering price of the total number of shares of Common Stock
                  so offered would purchase at such current market price, such
                  adjustment to become effective immediately after the opening
                  of business on the record date for the determination of
                  stockholders entitled to receive such rights or warrants. For
                  the purpose of any computation under this subsection (ii) or
                  subsection (iii) below, the current market price per share of
                  Common Stock at any record date shall be deemed to be the
                  average of the daily closing prices for the 30 consecutive
                  business days commencing 45 business days prior to the day in
                  question. The closing price per share of Common Stock for each
                  day shall be the last reported sale price regular way, or, in
                  case no such reported sale takes place on such day, the
                  average of the reported closing bid and asked prices regular
                  way in either case on the New York Stock Exchange, or, if the
                  Common Stock is not listed or admitted to business on such
                  Exchange, on the principal national securities exchange on
                  which the Common Stock is listed or admitted to business, or
                  if not listed or admitted to business on any



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                  national securities exchange, the average of the closing bid
                  and asked prices as furnished by the National Quotation
                  Bureau, Incorporated or similar organization if the National
                  Quotation Bureau, Incorporated is no longer reporting such
                  information.

                           (iii) If the Corporation distributes to holders of
                  its Common Stock evidences of indebtedness or securities or
                  cash or other assets (excluding regular quarterly cash
                  dividends or dividends payable in shares of Common Stock), the
                  conversion rate in effect immediately prior to the record date
                  mentioned below shall be adjusted by multiplying such
                  conversion rate by a fraction, of which the numerator shall be
                  the current market price per share of Common Stock on such
                  record date and of which the denominator shall be such current
                  market price per share of the Common Stock, less the cash or
                  the then fair market value (as determined by the Board of
                  Directors, whose determination shall be conclusive) of the
                  portion of the assets or securities or evidences of
                  indebtedness so distributed applicable to one share of Common
                  Stock, such adjustment to become effective immediately on the
                  record date for the determination of stockholders entitled to
                  receive such distribution. The reclassification (including any
                  reclassification upon a merger in which the Corporation is the
                  continuing corporation) of Common Stock into securities which
                  include both Common Stock and other securities shall be deemed
                  to involve (i) a distribution of such securities other than
                  Common Stock to all holders of Common Stock (and the effective
                  date of such reclassification shall be deemed to be "the
                  record date for the determination" above), and (ii) a
                  subdivision or combination, as the case may be, of the number
                  of shares of Common Stock outstanding immediately prior to
                  such reclassification into the number of shares of Common
                  Stock outstanding immediately thereafter.

                           (iv) In the event of a declaration of a dividend by
                  the Corporation without the fixing of a record date for the
                  determination of stockholders entitled thereto, the first
                  business day during which the stock transfer books of the
                  Corporation shall be closed for the purpose of such
                  determination shall be deemed to be the record date.

                  (E) No fractional shares of Common Stock shall be issued upon
         the conversion of shares of Series D Preferred Stock. If any fractional
         interest in a share of Common Stock would, except for the provisions of
         this Section 7(E), be deliverable upon the conversion of any shares of
         Series D Preferred Stock, the Corporation, in lieu of delivering a
         fractional share therefor, shall make a payment to the holder of such
         surrendered share of Series D Preferred Stock of an amount in cash
         equal (computed to the nearest cent) to such fraction multiplied by the
         closing price per share of Common Stock (as such term is defined in the
         final sentence of Section 7(D)(ii)) on the day of conversion.

                  (F) Whenever the conversion rate is adjusted, as herein
         provided, the Corporation shall forthwith deliver to each record holder
         of the Series D Preferred Stock a statement signed by the President or
         Vice President of the Corporation and by its Treasurer or an Assistant
         Treasurer, showing in detail the facts requiring such adjustment and
         the conversion rate after such adjustment.


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                  (G) In case of any capital reorganization or any
         reclassification of the Common Stock or in case of a consolidation,
         merger or statutory share exchange of the Corporation with or into
         another corporation or the conveyance of all or substantially all of
         the assets of the Corporation to another corporation, each share of
         Series D Preferred Stock shall thereafter be convertible into the
         number of shares of stock or other securities or property (including
         cash) to which a holder of the number of shares of Common Stock
         deliverable upon conversion of such shares of Series D Preferred Stock
         would have been entitled upon such reorganization, reclassification,
         consolidation, merger or conveyance; and, in any such case, appropriate
         adjustment (as determined by the Board of Directors) shall be made in
         the application of the provisions herein set forth with respect to the
         rights and interests thereafter of the holders of the shares of Series
         D Preferred Stock to the end that the provisions set forth herein
         (including provisions with respect to changes in and other adjustments
         of the conversion rate) shall thereafter be applicable, as nearly as
         reasonably may be, in relation to any shares of stock or other property
         thereafter deliverable upon the conversion of the shares of Series D
         Preferred Stock.

                  (H) In the event that:

                           (i) the Corporation shall take a record of the
                  holders of shares of its Common Stock for the purpose of
                  entitling them to receive a dividend, or any other
                  distribution, other than regular quarterly cash dividends; or

                           (ii) the Corporation shall take a record of the
                  holders of shares of its Common Stock for the purpose of
                  entitling them to subscribe for or purchase any shares of
                  stock of any class or to receive any other rights or warrants;
                  or

                           (iii) there shall be any capital reorganization of
                  the Corporation, reclassification of the Common Stock (other
                  than a subdivision or combination thereof), consolidation or
                  merger of the Corporation with or into another corporation or
                  the conveyance of all or substantially all of the assets of
                  the Corporation to another corporation; or

                           (iv) there shall be any voluntary or involuntary
                  dissolution, liquidation or winding up of the Corporation;

         then, and in any such case, the Corporation shall cause to be given to
         each record holder of Series D Preferred Stock, at least fifteen (15)
         days prior to the date hereinafter specified, or if notice is given to
         holders of Common Stock, no later than the date such notice is given, a
         notice stating the date on which (x) a record is to be taken for the
         purpose of such dividend, distribution or rights, or (y) such
         reclassification, reorganization, consolidation, merger, conveyance,
         dissolution, liquidation or winding up is to take place and the date,
         if any, that is to be fixed, as of which holders of shares of Common
         Stock of record shall be entitled to exchange their shares of Common
         Stock for securities or other property deliverable upon


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         such reclassification, reorganization, consolidation, merger,
         conveyance, dissolution, liquidation or winding up.

                  (I) The Corporation shall obtain and keep in force such
         permits or other authorizations as may be required by law in order to
         enable the Corporation validly to issue and deliver such number of
         shares of its Common Stock as shall from time to time be sufficient to
         effect the conversion of all shares of Series D Preferred Stock from
         time to time outstanding. The Corporation at all times shall reserve
         and keep available, out of its authorized but unissued Common Stock,
         solely for the purposes of effecting the conversion of the shares of
         Series D Preferred Stock, the full number of shares of Common Stock
         deliverable upon the conversion of all shares of Series D Preferred
         Stock from time to time outstanding.

                  (J) The Corporation shall pay any and all issue and other
         taxes that may be payable in respect of any issue or delivery of shares
         of Common Stock on conversion of shares of Series D Preferred Stock
         pursuant hereto.

         8. Parity With Respect to Dividends and Distribution Upon Liquidation.
The Series D Preferred Stock shall rank on a parity with any other series of
Preferred Stock, including the Pari Passu Stock, not by its terms made junior or
senior to the Series D Preferred Stock, with respect to the payment of dividends
and shall rank on a parity with any other series of Preferred Stock, including
the Pari Passu Stock, not by its terms made junior or senior to the Series D
Preferred Stock, as to distribution of assets in liquidation.

         9. Transfer of Series D Preferred Stock. The shares of the Series D
Preferred Stock shall not be transferable, either in whole or in part, unless
such shares have been publicly registered, subject to any agreement between any
holder of the Series D Preferred Stock and the Corporation to the contrary, or
the Corporation receives an opinion (or affirmatively waives its right to
receive such opinion) of transferee's or transferor's counsel stating that such
transfer is exempt from the registration and prospectus delivery requirements of
applicable securities laws.

         10. Notice to Holders. Any notice required to be given to any holder of
Series D Preferred Stock shall be mailed, postage prepaid, to such holder at
such holder's address last shown on the records of the Corporation.

         IN WITNESS WHEREOF, the undersigned has caused the Articles
Supplementary to be executed by its Executive Vice President - Finance and
witnessed by its Assistant Secretary this 9th day of December, 1999.

                                           CAPSTEAD MORTGAGE CORPORATION
Witness


By: /s/ DAVID S. BARBOUR                  By: /s/ ANDREW F. JACOBS
   --------------------------------------     ----------------------------------
    David S. Barbour, Assistant Secretary     Executive Vice President - Finance


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         THE UNDERSIGNED, Executive Vice President - Finance of THE CORPORATION,
who executed on behalf of the Corporation Articles Supplementary of which this
Certificate is made a part, hereby acknowledges in the name and on behalf of
said Corporation the foregoing Articles Supplementary to be the corporate act of
said Corporation and hereby certifies that the matters and facts set forth
herein with respect to the authorization and approval therefor are true in all
material respects under the penalties of perjury.

                                             /s/ ANDREW F. JACOBS
                                             -----------------------------------
                                             Executive Vice President - Finance




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