UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-8F

I. General Identifying Information

1. Reason fund is applying to deregister (check only one; for descriptions, see Instruction 1):

x Merger

¨ Liquidation

¨ Abandonment of Registration

(Note: Abandonments of Registration answer only questions 1 through 15, 24 and 25 of this form and complete verification at the end of the form.)

¨ Election of status as a Business Development Company

(Note: Business Development Companies answer only questions 1 through 10 of this form and complete verification at the end of the form.)

2. Name of fund: COLUMBIA MID CAP GROWTH FUND, INC. (the “Fund”)

3. Securities and Exchange Commission File No. 811-4362

4. Is this an initial Form N-8F or an amendment to a previously filed Form N-8F?

¨  Initial Application                x  Amendment

5. Address of Principal Executive Office (include No. & Street, City, State, Zip Code):

1301 SW Fifth Avenue

Portland, OR 97201

6. Name, address and telephone number of individual the Commission staff should contact with any questions regarding this form:

Brian D. McCabe, Esquire	Jacob E. Comer, Esquire
Ropes & Gray LLP	Ropes & Gray LLP
One International Place	One International Place
Boston, MA 02110	Boston, MA 02110
(617) 951-7801; or	(617) 951-7913

7. Name, address and telephone number of individual or entity responsible for maintenance and preservation of fund records in accordance with rules 31a-1 and 31a-2 under the Act [17 CFR 270.31a-1, .31a-2]:

(a) Columbia Management Advisors, LLC, 100 Federal Street, Boston, Massachusetts 02110, (800) 892-1127

(records relating to its functions as investment advisor, administrator and pricing and bookkeeping agent).

(b) Columbia Management Distributors, Inc., One Financial Center, Boston, MA 02111, (617) 772-3058

(records relating to its function as distributor).

(c) Columbia Management Services, Inc., One Financial Center, Boston, MA 02111, (617) 772-3480

(records relating to its function as shareholder services and transfer agent).

(d) State Street Bank & Trust Company, Two Avenue de Lafayette, LCC/4S, Boston, MA 02111, (617) 662-4100

(records relating to its function as custodian).

NOTE: Once deregistered, a fund is still required to maintain and preserve the records described in rules 31a-1 and 31a-2 for the periods specified in those rules.

8. Classification of fund (check only one):

x Management company;

¨ Unit investment trust; or

¨ Face-amount certificate company.

9. Subclassification if the fund is a management company (check only one):

x  Open-end                 ¨  Closed-end

10. State law under which the fund was organized or formed (e.g., Delaware, Massachusetts):

Oregon

11. Provide the name and address of each investment adviser of the fund (including sub-advisers) during the last five years, even if the fund’s contracts with those advisers have been terminated.

Columbia Management Advisors, LLC

100 Federal Street

Boston, MA 02110

12. Provide the name and address of each principal underwriter of the fund during the last five years, even if the fund’s contracts with those underwriters have been terminated:

Columbia Management Distributors, Inc.

One Financial Center

Boston, MA 02111

13. If the fund is a unit investment trust (“UIT”) provide:

(a) Depositor’s name(s) and address(es):	Not applicable.
(b) Trustee’s name(s) and address(es):	Not applicable.

14. Is there a UIT registered under the Act that served as a vehicle for investment in the fund (e.g., an insurance company separate account)?

¨  Yes    x  No

If Yes, for each UIT state:

Name(s):

File No.:

Business Address:

15. (a)    Did the fund obtain approval from the board of directors concerning the decision to engage in a Merger, Liquidation or         Abandonment of Registration?

x  Yes    ¨  No

If Yes, state the date on which the board vote took place:

May 11, 2005.

If No, explain:

(b) Did the fund obtain approval from the shareholders concerning the decision to engage in a Merger, Liquidation or Abandonment of Registration?

x  Yes    ¨  No

If Yes, state the date on which the shareholder vote took place: October 7, 2005.

If No, explain:

II. Distributions to Shareholders

16. Has the fund distributed any assets to its shareholders in connection with the Merger or Liquidation?

x  Yes    ¨  No

(a) If Yes, list the date(s) on which the fund made those distributions:

March 27, 2006.

(b) Were the distributions made on the basis of net assets?

x  Yes    ¨  No

(c) Were the distributions made pro rata based on share ownership?

x  Yes    ¨  No

(d) If No to (b) or (c) above, describe the method of distributions to shareholders. For Mergers, provide the exchange ratio(s) used and explain how it was calculated:

(e) Liquidations only:

Were any distributions to shareholders made in kind?

¨  Yes    ¨  No

If Yes, indicate the percentage of fund shares owned by affiliates, or any other affiliation of shareholders:

17. Closed-end funds only:

Has the fund issued senior securities?

¨  Yes    ¨  No

If Yes, describe the method of calculating payments to senior security holders and distributions to other shareholders:

18. Has the fund distributed all of its assets to the fund’s shareholders?

x  Yes    ¨  No

If No,

(a) How many shareholders does the fund have as of the date this form is filed?

(b) Describe the relationship of each remaining shareholder to the fund:

19. Are there any shareholders who have not yet received distributions in complete liquidation of their interests?

¨  Yes    x  No

If Yes, describe briefly the plans (if any) for distributing to, or preserving the interests of, those shareholders:

III. Assets and Liabilities

20. Does the fund have any assets as of the date this form is filed?

(See question 18 above)

¨  Yes    x  No

If Yes,

(a) Describe the type and amount of each asset retained by the fund as of the date this form is filed:

(b) Why has the fund retained the remaining assets?

(c) Will the remaining assets be invested in securities?

¨  Yes    ¨  No

21. Does the fund have any outstanding debts (other than face-amount certificates if the fund is a face-amount certificate company) or any other liabilities?

¨  Yes    x  No

If Yes,

(a) Describe the type and amount of each debt or other liability:

(b) How does the fund intend to pay these outstanding debts or other liabilities?

IV. Information About Event(s) Leading to Request For Deregistration

22. (a)    List the expenses incurred in connection with the Merger or Liquidation:

(i) Legal expenses: Approximately $6,689.00

(ii) Accounting expenses: $0.

(iii) Other expenses (list and identify separately):

Proxy solicitation expenses: Approximately $0.

Brokerage commissions: $0.

Audit expenses: $0.

Custody fees: $0.

SEC registration fees: $12,415.00.

(iv) Total expenses (sum of lines (i)-(iii) above): Approximately $19,103.00.

(b) How were those expenses allocated?

All expenses were allocated to Columbia Management Advisors, LLC.

(c) Who paid those expenses?

Columbia Management Advisors, LLC.

(d) How did the fund pay for unamortized expenses (if any)?

There were no unamortized expenses.

23. Has the fund previously filed an application for an order of the Commission regarding the Merger or Liquidation?

x  Yes    ¨  No

If Yes, cite the release numbers of the Commission’s notice and order or, if no notice or order has been issued, the file number and date the application was filed: File no. 811-04362; filed June 23, 2006.

V. Conclusion of Fund Business

24. Is the fund a party to any litigation or administrative proceeding?

x  Yes    ¨  No

If Yes, describe the nature of any litigation or proceeding and the position taken by the fund in that litigation:

On February 9, 2005, Columbia Management Advisors, Inc. (which has since merged into Banc of America Capital Management, LLC (now named Columbia Management Advisors, LLC)) (“Columbia”) and Columbia Funds Distributor, Inc. (which has been renamed Columbia Management Distributors, Inc.) (the “Distributor”) (collectively, the “Columbia Group”) entered into an Assurance of Discontinuance with the New York Attorney General (“NYAG”) (the “NYAG Settlement”) and consented to the entry of a cease- and-desist order by the Securities and Exchange Commission (“SEC”) (the “SEC Order”). The SEC Order

and the NYAG Settlement are referred to collectively as the “Settlements”. The Settlements contain substantially the same terms and conditions as outlined in the agreements in principle which Columbia Group entered into with the SEC and NYAG in March, 2004.

Under the terms of the SEC Order, the Columbia Group agreed among other things, to: pay $70 million in disgorgement and $70 million in civil money penalties; cease and desist from violations of the antifraud provisions and certain other provisions of the federal securities laws; maintain certain compliance and ethics oversight structures; retain an independent consultant to review the Columbia Group’s applicable supervisory, compliance, control and other policies and procedures; and retain an independent distribution consultant (see below). The Columbia Funds have also voluntarily undertaken to implement certain governance measures designed to maintain the independence of their boards of trustees. The NYAG Settlement also, among other things, requires Columbia and its affiliates to reduce management fees for certain Columbia Funds (including the former Nations Funds) and other mutual funds collectively by $32 million per year for five years, for a projected total of $160 million in management fee reductions.

Pursuant to the procedures set forth in the SEC order, the $140 million in settlement amounts described above will be distributed in accordance with a distribution plan developed by an independent distribution consultant and approved by the SEC. The independent distribution consultant has been in consultation with the staff of the SEC and has submitted a proposed plan of distribution. The SEC has not yet approved a final plan of distribution.

As a result of these matters or any adverse publicity or other developments resulting from them, there may be increased redemptions or reduced sales of fund shares, which could increase transaction costs or operating expenses, or have other adverse consequences for the funds.

A copy of the SEC Order is available on the SEC website at http://www.sec.gov. A copy of the NYAG Settlement is available as part of the Bank of America Corporation Form 8-K filing on February 10, 2005.

In connection with the events described in detail above, various parties have filed suit against certain funds, the Trustees of the Columbia Funds, FleetBoston Financial Corporation and its affiliated entities and/or Bank of America and its affiliated entities.

On February 20, 2004, the Judicial Panel on Multidistrict Litigation transferred these cases and cases against several other mutual fund companies based on similar allegations to the United States District Court in Maryland for consolidated or coordinated pretrial proceedings (the “MDL”). Subsequently, additional related cases were transferred to the MDL. On September 29, 2004, the plaintiffs in the MDL filed amended and consolidated complaints. One of these amended complaints is a putative class action that includes claims under the federal securities laws and state common law, and that names Columbia, the Distributor, the Trustees of the Columbia Funds, Bank of America Corporation and others as defendants. Another of the amended complaints is a derivative action purportedly on behalf of the Columbia Funds that asserts claims under federal securities laws and state common law.

On February 25, 2005, Columbia and other defendants filed motions to dismiss the claims in the pending cases. On March 1, 2006, for reasons stated in the court’s memoranda dated November 3, 2005, the U.S. District Court for the District of Maryland granted in part and denied in part the defendants’ motions to dismiss. The court dismissed all of the class action claims pending against the Columbia Funds Trusts and the Columbia Acorn Trust. As to Columbia, and the Distributor, the claims under the Securities Act of 1933, the claims under Sections 34(b) and 36(a) of the Investment Company Act of 1940 (“ICA”) and the state law claims were dismissed. The claims under Sections 10(b) and 20(a) of the Securities Exchange Act of 1934 and claims under Section 36(b) of the ICA along with related claims under Section 48(a) of the ICA were not dismissed.

On March 21, 2005, a purported class action was filed in Massachusetts state court alleging that the conduct, including market timing, entitles Class B shareholders in certain Columbia funds to an exemption from contingent deferred sales charges upon early redemption (“the CDSC Lawsuit”). The CDSC Lawsuit has been removed to federal court in Massachusetts and the federal Judicial Panel has transferred the CDSC Lawsuit to the MDL.

On April 4, 2006, the plaintiffs and the Columbia defendants named in the MDL, including the Columbia Funds, entered into a term sheet containing the principal terms of a stipulation of settlement that would settle all Columbia-related claims in the MDL described above, including the CDSC Lawsuit. On April 6, 2006, the U.S. District Court for the District of Maryland stayed all actions with respect to these Columbia-related claims.

The MDL is ongoing. Accordingly, an estimate of the financial impact of this litigation on any fund, if any, cannot currently be made.

In 2004, certain Columbia funds, the Trustees of the Columbia Funds, advisers and affiliated entities were named as defendants in certain purported shareholder class and derivative actions making claims, including claims under the Investment Company and the Investment Advisers Acts of 1940 and state law. The suits allege, inter alia, that the fees and expenses paid by the funds are excessive and that the advisers and their affiliates inappropriately used fund assets to distribute the funds and for other improper purpose. On March 2, 2005, the actions were consolidated in the Massachusetts federal court as In re Columbia Entities Litigation. The plaintiffs filed a consolidated amended complaint on June 9, 2005. On November 30, 2005, the judge dismissed all claims by plaintiffs and ordered that the case be closed. The plaintiffs filed a notice of appeal on December 30, 2005 and this appeal is pending.

25. Is the fund now engaged, or intending to engage, in any business activities other than those necessary for winding up its affairs?

¨  Yes    x  No

If Yes, describe the nature and extent of those activities:

VI. Mergers Only

26. (a)    State the name of the fund surviving the Merger: Columbia Mid Cap Growth Fund, a series of Columbia Funds Series         Trust I.

The names of the surviving portfolios are as follows:

Target Fund:	Survivor Fund:
Columbia Mid Cap Growth Fund, Inc.	Columbia Mid Cap Growth Fund, a series of Columbia Funds Series Trust I

(b) State the Investment Company Act file number of the fund surviving the Merger: 811-4367

(c) If the merger or reorganization agreement has been filed with the Commission, state the file number(s), form type used and date the agreement was filed: Not applicable.

(d) If the merger or reorganization agreement has not been filed with the Commission, provide a copy of the agreement as an exhibit to this form.

Attached as Exhibit A.

VERIFICATION

The undersigned states that (i) he has executed this Form N-8F application for an order under section 8(f) of the Investment Company Act of 1940 on behalf of Columbia Mid Cap Growth Fund, Inc., (ii) he is the Treasurer of Columbia Mid Cap Growth Fund, Inc., and (iii) all actions by shareholders, directors, and any other body necessary to authorize the undersigned to execute and file this Form N-8F application have been taken. The undersigned also states that the facts set forth in this Form N-8F application are true to the best of his knowledge, information and belief.

/s/ J. Kevin Connaughton

J. Kevin Connaughton

Treasurer