Exhibit
10.8

    


    AMENDMENT
AGREEMENT

    DATED
AS OF MARCH 24, 2008

    TO
THE MARKETING AGENT AGREEMENT

    DATED
AS OF APRIL 17, 2007

    


    AMENDMENT AGREEMENT (the
“Amendment”) dated as of March 24, 2008 between ALPS DISTRIBUTORS, INC.
(“ALPS”), VICTORIA BAY ASSET
MANAGEMENT, LLC (“VBAM”), and UNITED STATES NATURAL GAS FUND, LP
(“USNG”).

    


    WITNESSETH

     

    The
parties have previously entered into that certain Marketing Agent Agreement
dated as of April 17, 2007 (the “Agreement”).  The parties have agreed
to amend the Agreement in accordance with the terms of this
Amendment.

     

    NOW, THEREFORE, in consideration of the
mutual agreements herein contained, ALPS, VBAM and USNG hereby acknowledge and
agree as follows:

    


    1.           Amendment of the
Agreement.  Upon execution of this Amendment by ALPS, VBAM and
USNG, the Agreement shall be hereby amended as follows:

    


    
      	
               
      

            	
              (a)

            	
              Section
      8 of the Agreement, “Duration,” shall be deleted in its entirety and
      replaced with the following:

            


    

    


    Duration.  This
Agreement shall become effective on the date hereof and continue for an initial
term of one (1) year from the date of this Agreement and will include any
renewal term of this Agreement and will last until the expiration of this
Agreement or the earlier termination of this Agreement in accordance with its
terms (the “Term”). This Agreement will automatically be renewed for successive
one (1) year periods unless, no later than thirty (30) calendar days prior to
the end of the then-current Term, either the Marketing Agent, on the one hand,
or the General Partner, on the other hand, elects to terminate this Agreement by
delivering written notice thereof to the other party.  Upon the
completion of the initial term, either the Marketing Agent, on the one hand, or
the General Partner, on the other hand, may elect to terminate this Agreement by
delivering 90 days notice thereof to the other party.  Notwithstanding
the foregoing, this Agreement may be terminated by any party upon written notice
to the other parties if (a) the Fund is terminated, (b) any other party becomes
insolvent or bankrupt or files a voluntary petition, or is subject to an
involuntary petition, in bankruptcy or attempts to or makes an assignment for
the benefit of its creditors or consents to the appointment of a trustee or
receiver, provided that the General Partner may not terminate this Agreement
pursuant to this provision if the event relates to the General Partner or the
Fund or (c) any other party willfully and materially breaches its obligations
under this Agreement and such breach has not been cured to the reasonable
satisfaction of the non-breaching party prior to the expiration of ninety (90)
days after notice by the non-breaching party to the breaching party of such
breach.

    


    (b)           All
references in the Agreement to the “National Association of Securities Dealers,
Inc.” shall be replaced with the “Financial Industry Regulatory Authority” and
all references to the “NASD” shall be replaced with “FINRA.”


    
      
         


      

      
         


        
          

        

      

      
         


      

    


    2.           Representations.  Each
party represents to the other party that:-

    


    (a)           Status.  It is duly
organized and validly existing under the laws of the jurisdiction of its
organization or incorporation and, if relevant under such laws, in good
standing;

    


    (b)           Powers. It has the power to
execute and deliver this Amendment and has taken all necessary action to
authorize such execution, delivery and performance;

    


    (c)           No Violation or Conflict. Such
execution, delivery and performance do not violate or conflict with any law
applicable to it, any provision of its constitutional documents, any order or
judgment of any court or other agency of government applicable to it or any of
its assets or any contractual restriction binding on or affecting it or any of
its assets;

    


    (d)           Consents.  All
governmental and other consents that are required to

    have been
obtained by it with respect to this Amendment have been obtained and are in full
force and effect and all conditions of any such consents have been complied
with; and

    


    (e)           Obligations
Binding.  Its obligations under this Amendment
constitute

    its
legal, valid and binding obligations, enforceable in accordance with its
respective terms (subject to applicable bankruptcy, reorganization, insolvency,
moratorium or similar laws affecting creditors’ rights generally and subject, as
to enforceability, to equitable principles of general application (regardless of
whether enforcement is sought in a proceeding in equity or at
law)).

    


    3.           Miscellaneous.

    


    (a)           Entire
Agreement.  The Amendment constitutes the entire agreement and
understanding of the parties with respect to its subject matter and supersedes
all oral communication and prior writings (except as other wise provided herein)
with respect thereto.

    


    (b)           Counterparts.  This
Amendment may be signed in any number of counterparts, each of which shall be an
original, with the same effect as if signatures thereto and hereto were upon the
same instrument.

    


    (c)           Headings.  The
headings used in this Amendment are for convenience of reference only and are
not to affect the construction of or to be taken into consideration in
interpreting this Amendment.

    


    (d)           Governing Law.  This
Amendment shall be governed by and construed in accordance with the laws of the
State of New York (without reference to choice of law doctrine).

    


    (e)           Terms. Terms used in this
Amendment, unless otherwise defined herein, shall have the meanings ascribed to
them in the Agreement.


    
      
         


      

      
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    IN
WITNESS WHEREOF, the parties have caused this Amendment to be executed by their
respective officers or authorized representatives as of the day and year first
above written.

    


    
      
        
          
            
              
                	
                        ALPS
      DISTRIBUTORS, INC.

                      	
                        VICTORIA
      BAY ASSET

                        MANAGEMENT,
      LLC

                      
	 
      	 
      	 
      	 
	
                        By:

                      	
                        /s/ Thomas A. Carter

                      	 
      	
                        By:

                      	
                        /s/ Howard Mah

                      	 
	
                        Name:
      Thomas A. Carter

                      	 
      	
                        Name:
      Howard Mah

                      	 
	
                        Title:
      Managing Director

                         
      Business Development

                      	 
      	
                        Title:
      Management Director

                      	 
	 
      	 
      	
                        Date:
      April 29, 2008

                      	 


              

            

          

        

      

    

    


    
      
        
          
            
              	 
      	
                      UNITED
      STATES NATURAL GAS

                    
	 
      	
                      FUND,
      LP

                    	 
	 
      	 
      	 
	 
      	
                      By:

                    	
                      /s/ Howard Mah

                    	 
	 
      	
                      Name:  
      Howard Mah

                    	 
	 
      	
                      Title:    
      Management Director

                    	 
	 
      	
                      Date:
      April 29, 2008

                    	 


            

          

        

      

    


    
      
         


      

      
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