THE DOW CHEMICAL COMPANY 4.85% Notes due 2012

Exhibit 4.1

UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (55 WATER STREET, NEW YORK, NEW YORK) (THE “DEPOSITORY”) TO THE ISSUER OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED 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 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.

THE DOW CHEMICAL COMPANY

4.85% Notes due 2012

CUSIP NO. 260543 BZ 5

ISIN NO. US260543BZ51

THE DOW CHEMICAL COMPANY, a Delaware corporation (herein called the “Company,” which term includes any successor corporation under the Indenture hereinafter referred to), for value received, hereby promises to pay to CEDE & CO., or registered assigns, the principal sum of [                                ] DOLLARS (US$[                    ]) on August 15, 2012, in such coin or currency of the United States of America as at the time of payment shall be legal tender for the payment of public and private debts, and to pay interest thereon semi-annually on each February 15 and August 15 (each an “Interest Payment Date”), commencing February 15, 2010 and at maturity on said principal sum, in such coin or currency of the United States of America as at the time of payment shall be legal tender for the payment of public and private debts, at the rate per annum specified in the title of this Security, or as may be adjusted pursuant to the terms hereof, from the February 15 or August 15, as the case may be, next preceding the date of this Security to which interest has been paid, unless the date hereof is a date to which interest has been paid, in which case from the date of this Security, or unless no interest has been paid on this Security, in which case from August 7, 2009, until payment of said principal sum has been made or duly provided for. Payments of such principal and interest shall be made at the office or agency of the Company in Chicago, Illinois, which, subject to the right of the Company to vary or terminate the appointment of such agency, shall initially be at the principal office of The Bank of New York Mellon Trust Company, N.A., Two North LaSalle Street, Chicago, Illinois 60602; provided , that payment of interest may be made at the option of the Company by check mailed to the address of the person entitled thereto as such address shall appear on the Security register; provided , further that so long as CEDE & CO. or another nominee of the Depository is the registered owner of this Security payments of principal and interest will be made in immediately available funds through the Depository’s Same-Day Funds Settlement System.

Notwithstanding the foregoing, if the date hereof is after February 1 or August 1, as the case may be, and before the following February 15 or August 15, this Security shall bear interest from such February 15 or August 15; provided , that if the Company shall default in the payment of interest due on such February 15 or August 15, then this Security shall bear interest from the next preceding February 15 or August 15, to which interest has been paid or, if no interest has been paid on this Security, from August 7, 2009. The interest payable on any February 15 or August 15 will, subject to certain exceptions provided in the Indenture referred to on the reverse hereof, be paid to the person in whose name this Security is registered at the close of business on the February 1 or August 1 (each a “Record Date”), as the case may be, next preceding such February 15 or August 15, and the interest payable at maturity will be payable to the person to whom the principal hereof shall be payable.

Reference is made to the further provisions of this Security set forth on the reverse hereof. Such further provisions shall for all purposes have the same effect as though fully set forth at this place.

This Security shall not be valid or become obligatory for any purpose until the certificate of authentication hereon shall have been signed by the Trustee under the Indenture referred to on the reverse hereof.

[Signatures appear on next page]

IN WITNESS WHEREOF, THE DOW CHEMICAL COMPANY has caused this instrument to be signed by facsimile by its duly authorized representative.

Dated: August 7, 2009

TRUSTEE’S CERTIFICATE OF AUTHENTICATION

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

THE DOW CHEMICAL COMPANY

4.85% Notes due 2012

Section 1. General . This Note is one of a duly authorized issue of securities of the Company (herein called the “Securities”), issued and to be issued in one or more series under an Indenture, dated as of May 1, 2008 (the “Indenture”), between The Dow Chemical Company (the “Company”) and The Bank of New York Mellon Trust Company, N.A., as trustee (herein called the “Trustee”, which term includes any successor trustee under the Indenture), to which Indenture and all indentures supplemental thereto reference is hereby made for a statement of the respective rights, limitations of rights, duties 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. This Security is one of the Securities of the series designated on the face hereof.

Section 2. Interest Rate Adjustment . The interest rate payable on this Security shall be subject to adjustments from time to time if either Moody’s (as defined below) or S&P (as defined below) or, if either Moody’s or S&P ceases to rate the Securities or fails to make a rating of the Securities publicly available for reasons outside of the Company’s control, a “nationally recognized statistical rating organization” within the meaning of Rule 15c3-1(c)(2)(vi)(F) under the Exchange Act, selected by us as a replacement agency for Moody’s or S&P (a “substitute rating agency”) downgrades (or subsequently upgrades) the credit rating assigned to the Securities, in the manner described below.

If the rating from Moody’s (or any substitute rating agency thereof) of the Securities is decreased to a rating set forth in the immediately following table, the interest rate on this Security will increase such that it will equal the interest rate set forth on the face of this Security plus the percentage set forth opposite the ratings from the table below:

If the rating from S&P (or any substitute rating agency thereof) of the Securities is decreased to a rating set forth in the immediately following table, the interest rate on this Security will increase such that it will equal the interest rate set forth on the face of this Security plus the percentage set forth opposite the ratings from the table below:

If at any time the interest rate on this Security has been adjusted upward and either Moody’s or S&P (or, in either case, a substitute rating agency thereof), as the case may be, subsequently increases its rating of the Securities to any of the threshold ratings set forth above, the interest rate on this Security will be decreased such that the interest rate for this Security equals the interest rate set forth on the face of this Security plus the percentages set forth opposite the ratings from the tables above in effect immediately following the increase in rating. If Moody’s (or any substitute rating agency thereof) subsequently increases its rating of the Securities to Baa3 (or its equivalent, in the case of a substitute rating agency) or higher, and S&P (or any substitute rating agency thereof) increases its rating to BBB- (or its equivalent, in the case of a substitute rating agency) or higher the interest rate on this Security will be decreased to the interest rate set forth on the face of this Security. In addition, the interest rates on this Security will permanently cease to be subject to any adjustment described above (notwithstanding any subsequent decrease in the ratings by either or both rating agencies) if the Securities become rated A-3 and A- (or the equivalent of either such rating, in the case of a substitute rating agency) or higher by Moody’s and S&P (or, in either case, a substitute rating agency thereof), respectively (or one of these ratings if the Securities are only rated by one rating agency).

Each adjustment required by any decrease or increase in a rating set forth above, whether occasioned by the action of Moody’s or S&P (or, in either case, a substitute rating agency thereof), shall be made independent of any and all other adjustments. In no event shall (1) the interest rate for this Security be reduced to below the interest rate set forth on the face of this Security or (2) the total increase in the interest rate on this Security exceed 2.00% above the interest rate set forth on the face of this Security.

No adjustments in the interest rate of the Securities shall be made solely as a result of a rating agency ceasing to provide a rating of the Securities. If at any time fewer than two rating agencies provide a rating of the Securities for a reason beyond the Company’s control, the Company will use its commercially reasonable efforts to obtain a rating of the Securities from a substitute rating agency, to the extent one exists, and if a substitute rating agency exists, for purposes of determining any increase or decrease in the interest rate on this Security pursuant to the tables above (a) such substitute rating agency will be substituted for the last rating agency to provide a rating of the Securities but which has since ceased to provide such rating, (b) the relative rating scale used by such substitute rating agency to assign ratings to senior unsecured debt will be determined in good faith by the Company and, for purposes of determining the applicable ratings included in the applicable table above with respect to such substitute rating agency, such ratings will be deemed to be the equivalent ratings used by Moody’s or S&P, as applicable, in such table and (c) the interest rate on this Security will increase or decrease, as the case may be, such that the interest rate equals the interest rate set forth on the face of this Security plus the appropriate percentage, if any, set forth opposite the rating from such substitute rating agency in the applicable table above (taking into account the provisions of clause (b) above) (plus any applicable percentage resulting from a decreased rating by the other rating agency). For so long as only one rating agency provides a rating of the Securities, any subsequent increase or decrease in

the interest rate of the Securities necessitated by a reduction or increase in the rating by the agency providing the rating shall be twice the percentage set forth in the applicable table above. For so long as none of Moody’s, S&P or a substitute rating agency provides a rating of the Securities, the interest rate on this Security will increase to, or remain at, as the case may be, 2.00% above the interest rate set forth on the face of this Security.

Any interest rate increase or decrease described above will take effect from the first day of the interest period commencing after the date on which a rating change occurs that requires an adjustment in the interest rate. If Moody’s or S&P (or, in either case, a substitute rating agency thereof) changes its rating of the Securities more than once during any particular interest period, the last change by such agency will control for purposes of any interest rate increase or decrease with respect to the Securities described above relating to such rating agency’s action.

If the interest rate payable on this Security is increased as described above the term “interest,” as used with respect to this Security, will be deemed to include any such additional interest unless the context otherwise requires.

Section 3. Redemption; Sinking Fund . (a) Except as provided in paragraph (b) below, the Securities are not redeemable prior to maturity.

(b) The Securities are redeemable, at any time in whole or from time to time in part, at the option of the Company at a redemption price equal to the greater of:

(i) 100% of the principal amount of the Securities to be redeemed on that redemption date; and

(ii) the sum of the present values of the remaining scheduled payments of principal and interest on the Securities being redeemed on that redemption date (not including any portion of such payments of interest accrued as of the date of redemption), discounted to the date of redemption on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) at the Treasury Rate (as defined below), plus 50 basis points,

plus, in each case, accrued and unpaid interest thereon to the date of redemption.

Notwithstanding the foregoing, installments of interest on Securities that are due and payable on interest payment dates falling on or prior to a redemption date will be payable on the Interest Payment Date to the registered Holders as of the close of business on the relevant Record Date according to this Security and the Indenture.

“Comparable Treasury Issue” means the United States Treasury security selected by the Quotation Agent as havin