UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                                  SCHEDULE 13D
                   Under the Securities Exchange Act of 1934
                                (Amendment No. 9)*


                          AEOLUS PHARMACEUTICALS, INC.
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                                (Name of Issuer)

                    Common Stock, par value $0.01 per share
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                         (Title of Class of Securities)

                                    45325S-10-1
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                                 (CUSIP Number)

                                  Mary L. King
                         Xmark Opportunity Partners, LLC
                           90 Grove Street, Suite 201
                              Ridgefield, CT 06877
                                 (646) 688-5728
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                 (Name, Address and Telephone Number of Person
                Authorized to Receive Notices and Communications)

                                  April 18, 2007
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             (Date of Event which Requires Filing of this Statement)


If the filing person has previously  filed a statement on Schedule l3G to report
the  acquisition  that is the subject of this  Schedule  13D, and is filing this
schedule  because of Sections 240.13d-1(e), 240.13d-1(f)  or 240.13d-1(g), check
the following box. [  ]

Note:  Schedules  filed in paper format shall include a signed original and five
copies of the schedule, including all exhibits.  See Section 240.13d-7 for other
parties to whom copies are to be sent.

* The remainder of this cover page shall be filled out for a reporting  person's
initial filing on this form with respect to the subject class of securities, and
for  any  subsequent   amendment   containing   information  which  would  alter
disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the  Securities  Exchange  Act of
1934 ("Act") or otherwise  subject to the liabilities of that section of the Act
but  shall be  subject  to all other  provisions  of the Act  (however,  see the
Notes).





Cusip No.       45325S-10-1
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1.  Names of Reporting Persons.  I.R.S. Identification Nos. of above persons
    (entities only):
                        Xmark Opportunity Partners, LLC
                                 20-2052197
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2.  Check the Appropriate Box if a Member of a Group (See Instructions):
         (a)   Not
         (b)  Applicable
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3.  SEC Use Only

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4.  Source of Funds (See Instructions):  AF, WC
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5.  Check if Disclosure  of Legal Proceedings Is Required Pursuant to Items 2(d)
    or 2(e):               Not Applicable
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6.  Citizenship or Place of Organization:    United States

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    Number of                      7. Sole Voting Power:             14,344,435*
                                     -------------------------------------------
    Shares Beneficially            8. Shared Voting Power:                    *
                                     -------------------------------------------
    Owned by
    Each Reporting                 9. Sole Dispositive Power:        13,344,435*
                                      ------------------------------------------
    Person With                    10. Shared Dispositive Power:              *
                                      ------------------------------------------
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11. Aggregate Amount Beneficially Owned by Each Reporting Person:   14,344,435*

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12. Check if  the Aggregate  Amount in  Row (11) Excludes  Certain  Shares  (See
    Instructions):         Not Applicable
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13. Percent of Class Represented by Amount in Row (11):   45.6%*
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14. Type of Reporting Person (See Instructions):  IA
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* Xmark Opportunity Partners, LLC ("Opportunity Partners") is the sole member of
the  investment  manager of Xmark  Opportunity  Fund,  L.P., a Delaware  limited
partnership  ("Opportunity  LP"),  and Xmark  Opportunity  Fund,  Ltd., a Cayman
Islands exempted company ("Opportunity Ltd"), and, as such, possesses sole power
to vote and direct the disposition of all securities of Aeolus  Pharmaceuticals,
Inc.,  a  Delaware  corporation  (the  "Company"),  held by  Opportunity  LP and
Opportunity  Ltd.  Opportunity  Partners is the  investment  manager of Xmark JV
Investment Partners,  LLC, a Delaware limited liability company ("JV Partners"),
and, as such,  possesses  sole power to vote and direct the  disposition  of all
securities of the Company held by JV Partners.  Opportunity Partners is the sole
manager  of  Goodnow  Capital,  L.L.C.,  a Delaware  limited  liability  company
("Goodnow"),  and,  as  such,  possesses  sole  power  to vote  and  direct  the
disposition of all  securities of the Company held by Goodnow.  Mitchell D. Kaye
and David C. Cavalier,  the Chief Executive Officer and Chief Operating Officer,
respectively, of Xmark Capital Partners, LLC, the Managing Member of Opportunity
Partners,  share  voting and  investment  power with  respect to all  securities
beneficially owned by Opportunity Partners.

As of April 18, 2007,  Opportunity  LP held 2,783,286  common shares,  $0.01 par
value per share (the "Common Shares"), of the Company,  which includes 1,276,435
Common  Shares of the Company  owned by Goodnow,  and warrants to purchase up to
660,000 Common Shares of the Company at an exercise price of $0.50 per share. As
of April 18, 2007,  Opportunity Ltd held 5,437,537 Common Shares of the Company,
which  includes  3,300,653  Common Shares of the Company  owned by Goodnow,  and
warrants to purchase up to 990,000  Common  Shares of the Company at an exercise
price of $0.50 per share.  As of April 18,  2007,  JV  Partners  held  1,023,731
Common  Shares of the  Company and  warrants  to  purchase up to 500,000  Common
Shares  of the  Company  at an  exercise  price of $0.50 per  share.  All of the
warrants held by Opportunity LP, Opportunity Ltd and JV Partners are exercisable
within 60 days of the date of event which  required the filing of this Amendment
No. 9 to Schedule  13D. As of April 18,  2007,  Goodnow  held  3,529,951  Common
Shares of the Company in addition to the Common Shares of the Company referenced
above.  As of  April  18,  2007,  Opportunity  Partners  had the  right  to vote
1,000,000  Common  Shares of the Company  pursuant to a voting  trust  agreement
between  Opportunity  Partners  and the holders of record of the  shares.  As of
April 18,  2007,  David C.  Cavalier  held 70,000  Common  Shares of the Company
issuable upon the exercise of options held by Mr. Cavalier.

Based upon  information set forth in the Company's most recent  Quarterly Report
on Form 10-Q, as filed with the Securities  and Exchange  Commission on February
9,  2007,  there  were  29,286,082  Common  Shares  of the  Company  issued  and
outstanding as of February 7, 2007. As a result of the  foregoing,  for purposes
of Reg. Section  240.13d-3,  Opportunity  Partners is deemed to beneficially own
14,344,435  Common  Shares of the Company,  or 45.6% of the Common Shares of the
Company deemed issued and outstanding as of April 18, 2007.


Item 1.   Security and Issuer.
          -------------------

          This Item 1 is hereby  amended and restated to read in its entirety as
follows:

          "The class of equity  securities to which this Schedule 13D relates is
the common  stock,  par value $0.01 per share (the "Common  Shares"),  of Aeolus
Pharmaceuticals,  Inc., a Delaware  corporation (the "Company").  The address of
the principal  executive offices of the Company is 23811 Inverness Place, Laguna
Niguel, California 92677."


Item 2.   Identity and Background.
          ------------------------

          This Item 2 is hereby  amended and restated to read in its entirety as
follows:

          "The person filing this statement is Xmark Opportunity Partners,  LLC,
a Delaware limited liability company ("Opportunity  Partners"),  whose principal
address  is  90  Grove  Street,  Suite  201,   Ridgefield,   Connecticut  06877.
Opportunity  Partners has previously  filed Schedule 13D and amendments  thereto
jointly with Xmark Asset  Management,  LLC, a New York limited liability company
("Xmark Asset  Management").  However,  Xmark Asset  Management has ceased to do
business,  making  Opportunity  Partners  the sole  filing  person.  Opportunity
Partners is the sole member of the investment manager of Xmark Opportunity Fund,
L.P., a Delaware limited  partnership  ("Opportunity LP"), and Xmark Opportunity
Fund, Ltd., a Cayman Islands exempted company ("Opportunity Ltd"), and, as such,
possesses sole power to vote and direct the disposition of all securities of the
Company held by Opportunity LP and Opportunity Ltd.  Opportunity Partners is the
investment  manager of Xmark JV  Investment  Partners,  LLC, a Delaware  limited
liability   company  ("JV  Partners"  and,  together  with  Opportunity  LP  and
Opportunity  Ltd, the "Funds"),  and, as such,  possesses sole power to vote and
direct the disposition of all securities of the Company held by JV Partners. The
Funds are engaged in the investment in property of all kinds, including, without
limitation,   capital  stock,   depository   receipts,   investment   companies,
subscriptions,  warrants, bonds, notes, debentures, options and other securities
of whatever kind and nature. Opportunity Partners is the sole manager of Goodnow
Capital, L.L.C., a Delaware limited liability company ("Goodnow"), and, as such,
possesses sole power to vote and direct the disposition of all securities of the
Company held by Goodnow.

          Mitchell D. Kaye and David C. Cavalier,  the Chief  Executive  Officer
and Chief Operating Officer,  respectively,  of Xmark Capital Partners, LLC, the
Managing Member of Opportunity Partners,  share voting and investment power with
respect  to all  securities  beneficially  owned by  Opportunity  Partners.  Mr.
Cavalier is the Chairman of the Board of Directors of the Company.

          None of Opportunity  Partners,  the Funds, or Messrs. Kaye or Cavalier
ever has been convicted in any criminal proceeding (excluding traffic violations
or similar misdemeanors), and none ever has been a party to any civil proceeding
commenced before a judicial or administrative body of competent  jurisdiction as
a result of which  it/he was or is now  subject to a  judgment,  decree or final
order  enjoining  future  violations of, or prohibiting or mandating  activities
subject  to,  federal or state  securities  laws or finding any  violation  with
respect to such laws.  Messrs.  Kaye and  Cavalier  are  citizens  of the United
States."


Item 3.   Source and Amount of Funds or Other Consideration.
          -------------------------------------------------

          Item 3 of the  Schedule  13D is hereby  further  amended by adding the
following at the end thereof:

          "See Item 5 for further information."


Item 4.   Purpose of Transaction.
          -----------------------

          This Item 4 is hereby  amended and restated to read in its entirety as
follows:

          "The  acquisition  of the  securities  referred  to  herein is for the
purpose of having the ability to direct the strategic course of the Company. The
person filing this  statement has no present  intention to direct the day-to-day
management and affairs of the Company. However, through the covenants in various
financing  transaction  documents entered into among the Company,  the Funds and
Goodnow,  and  previously  disclosed  on  the  initial  Schedule  13D  filed  by
Opportunity  Partners  jointly with Xmark Asset  Management on December 1, 2003,
and its ability to elect a majority of the Board of  Directors of the Company by
virtue of its stock  ownership,  the filing person has the ability,  but not the
present  intention,  to direct  the  day-to-day  management  and  affairs of the
Company.

          David  C.  Cavalier,   the  Chief  Operating  Officer  of  Opportunity
Partners, is currently the Chairman of the Board of Directors of the Company.

          Other than as  described  above in this Item 4,  Opportunity  Partners
does not have any present plans or  intentions  which relate to, or would result
in, any of the transactions required to be described in Item 4 of Schedule 13D."


Item 5.   Interest in Securities of the Issuer.
          ------------------------------------

          This Item 5 is hereby  amended and restated to read in its entirety as
follows:

          "Based  upon  information  set  forth  in the  Company's  most  recent
Quarterly  Report  on Form  10-Q,  as filed  with the  Securities  and  Exchange
Commission  on  February 9, 2007,  there were  29,286,082  Common  Shares of the
Company issued and outstanding as of February 7, 2007.

          As of April 18, 2007,  Opportunity  LP held  2,783,286  common shares,
$0.01 par value per share (the "Common Shares"), of the Company,  which includes
1,276,435  Common  Shares of the  Company  owned by  Goodnow,  and  warrants  to
purchase up to 660,000  Common  Shares of the  Company at an  exercise  price of
$0.50 per share.  As of April 18, 2007,  Opportunity  Ltd held 5,437,537  Common
Shares of the Company,  which  includes  3,300,653  Common Shares of the Company
owned by Goodnow,  and warrants to purchase up to 990,000  Common  Shares of the
Company  at an  exercise  price of $0.50 per  share.  As of April 18,  2007,  JV
Partners held 1,023,731 Common Shares of the Company and warrants to purchase up
to 500,000 Common Shares of the Company at an exercise price of $0.50 per share.
All of the warrants held by Opportunity LP,  Opportunity Ltd and JV Partners are
exercisable  within 60 days of the date of event  which  required  the filing of
this  Amendment  No. 9 to  Schedule  13D.  As of April 18,  2007,  Goodnow  held
3,529,951  Common  Shares of the Company in addition to the Common Shares of the
Company  referenced  above. As of April 18, 2007,  Opportunity  Partners had the
right to vote 1,000,000  Common Shares of the Company pursuant to a voting trust
agreement between Opportunity Partners and the holders of record of the shares.

          Opportunity  Partners  possesses  sole  power to vote and  direct  the
disposition  of all  securities  of the Company  held by the Funds and  Goodnow.
Messrs.  Kaye and Cavalier share voting and investment power with respect to all
securities beneficially owned by Opportunity Partners. As of April 18, 2007, Mr.
Cavalier  held 70,000  Common  Shares of the Company  issuable  upon exercise of
options held by Mr. Cavalier.

          As a result of the foregoing,  for purposes of Reg. Section 240.13d-3,
Opportunity  Partners is deemed to beneficially own 14,344,435  Common Shares of
the  Company,  or 45.6% of the Common  Shares of the Company  deemed  issued and
outstanding as of April 18, 2007.

          During  the  sixty  (60)  days on or  prior  to April  18,  2007,  the
below-listed  transactions  in the Common  Shares of the Company,  or securities
exercisable  for  Common  Shares of the  Company,  were  consummated  by persons
referenced in Item 2. More specifically, all of the below-listed transactions in
the Common Shares of the Company were effected by Opportunity LP and Opportunity
Ltd in ordinary brokerage transactions.

Date        Number of Shares     Security Type      Purchase Price per Share ($)


4/18/2007      20,000            Common Shares              0.6088

4/18/2007      41,000            Common Shares              0.6256


          Except  for  the  transactions  listed  above,  none  of  the  persons
referenced in Item 2 traded securities of the Company during the sixty (60) days
on or prior to April 18, 2007.

          In  addition to the  above-listed  transactions,  on August 31,  2006,
Xmark Fund, L.P., a Delaware limited partnership, and Xmark Fund, Ltd., a Cayman
Islands exempted company (together,  the "Xmark Funds"),  transferred all of the
securities of the Company held by them to  Opportunity LP and  Opportunity  Ltd.
The disclosed number of Common Shares of the Company  collectively held by Xmark
Funds  and the Funds did not  change as a result of these  transfers.  The Xmark
Funds ceased to do business subsequent to the transfer."


Item 6.   Contracts, Arrangements, Understandings or Relationships with  Respect
          to Securities of the Issuer.
          ----------------------------------------------------------------------

          No material change.

Item 7.   Material to be Filed as Exhibits.
          --------------------------------

          Not applicable.







                                   Signature
                                   ---------

          After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information  set forth in this statement is true,  complete and
correct.


March 14, 2008                        XMARK OPPORTUNITY PARTNERS, LLC
                                      By:  XMARK CAPITAL PARTNERS, LLC
                                           its Managing Member

                                      By:  /s/ Mitchell D. Kaye
                                           -------------------------------------
                                          Name:  Mitchell D. Kaye
                                          Title: Chief Executive Officer



  Attention: Intentional misstatements or omissions of fact constitute Federal
                   criminal violations (See 18 U.S.C. 1001).