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                                                      EXHIBIT  10.42
                                   
                                    GUARANTY


         THIS GUARANTY AGREEMENT (this "Guaranty") is made this 6th day of July,
1998, by JENNIFER BARCLAY, of Bucks County, Pennsylvania (the "Guarantor") in
favor of UPPER MILL, L.P.

                        W I T N E S S E T H   T H A T :

         WHEREAS, a certain Lease Agreement dated December 16, 1996, by and
between WILLIAM I. ROBERTS, herein referred to as "Roberts", and BLUE FISH
CLOTHING, INC., herein referred to as "Blue Fish", as amended by the first
Addendum to Lease Agreement dated May 19, 1997, as assigned by Roberts to Upper
Mill, L.P. herein referred to as "Upper Mill" on October 21, 1997 and as amended
by the Second Addendum to Lease Agreement dated as of December 31, 1997 (the
"Lease") has been executed; and

         WHEREAS, by letter agreement dated July 6, 1998 (the "Letter
Agreement") Upper Mill and Blue Fish agreed to terminate the Lease effective
July 6, 1998 and release each other of all obligations under the Lease in
consideration of certain payments by Blue Fish to Upper Mill and the issuance of
the Blue Fish's Common Stock to Roberts all as set forth in the Letter
Agreement; and

         WHEREAS, Guarantor agreed as a condition to the execution of said
Letter Agreement to guaranty the performance of the obligations of Blue Fish
thereunder as set forth therein; and

         WHEREAS, the Letter Agreement is and will be to the financial interest
and advantage of Guarantor; and

         WHEREAS, Upper Mill was willing to enter into the Letter Agreement only
if Guarantor guaranteed the performance of each and all of the terms, covenants
and conditions of said Letter Agreement to be kept and performed by Blue Fish,
including the payments to Upper Mill as listed therein, on the terms and
conditions and for the maximum amount and for the duration set forth herein.

         NOW, THEREFORE, in consideration of the foregoing, and intending to be
legally bound hereby, Grantor covenants and agrees as follows:


         RECITALS INCORPORATED. Guarantor acknowledges and agrees that the
foregoing recitals constitute a material part of this Guaranty, and the same are
expressly incorporated herein by this reference.

         MATERIAL INDUCEMENT. Guarantor acknowledges and agrees that Upper Mill
would not have entered into the Letter Agreement without the execution of this
Guaranty by Guarantor, and that this Guaranty constitutes a material inducement
to Upper Mill's entering into the Letter Agreement with Blue Fish.

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         AMOUNT AND DURATION OF GUARANTY. This Guaranty shall be limited to
$180,000. The Guaranty amount shall be reduced to $142,000 when Blue Fish makes
a payment of $38,000 which is due to Upper Mill on June 30, 1999 pursuant to the
Letter Agreement. This Guaranty shall terminate and shall be rendered null and
void when Blue Fish makes the final payment of $40,000, which is due to Upper
Mill on June 30, 2000, or at such earlier time as all of the Blue Fish's
payments to the Upper Mill pursuant to the Letter Agreement have been made. Upon
termination of this Guaranty, the original and all copies thereof made by Upper
Mill and Roberts shall be returned to Guarantor.

         GUARANTY. Guarantor hereby personally, unconditionally, and irrevocable
guaranties the full performance of each and all of the terms, covenants and
conditions of said Letter Agreement to be performed by Blue Fish, including the
full prompt payment of all amounts to be paid thereunder and the performance of
all obligations in favor of Upper Mill and Roberts pursuant to the Letter
Agreement, subject to the limitations in Section 3. This Guaranty will continue
unchanged by: (i) any bankruptcy, reorganization or insolvency of Blue Fish or
any successor or assignee thereof or by any disaffirmance or abandonment by a
trustee of Blue Fish, and/or (ii) any transfer or other disposition of
Guarantor's interest in Blue Fish.

         RIGHTS OF MODIFICATION. This covenant and agreement on Guarantor's part
shall constitute a guaranty in favor of Upper Mill notwithstanding any
extension, modification, or alteration of said Letter Agreement entered into by
and between the parties thereto, or their successors or assigns, and no
extension, modification, alteration or assignment of the Letter Agreement shall
in any manner release or discharge the Guarantor, unless otherwise agreed to by
the parties.

         NATURE OF GUARANTY. The liability of Guarantor under this Guaranty,
shall be contingent on pursuit by Upper Mill of any remedies it may have against
Blue Fish or Blue Fish's successors or assigns, with respect to the Letter
Agreement, whether pursuant to the terms thereof or by law; provided, however,
that Upper Mill may enforce this Guaranty if demand is first made upon the Blue
Fish and such demand is not satisfied in full within fifteen (15) days after
such demand is made by notice given as provided herein.

         NO IMPAIRMENT OF GUARANTOR'S OBLIGATIONS. No course of dealing between
Upper Mill and Blue Fish, nor any failure or delay on the part of Upper Mill to
exercise any of Upper Mill's rights and remedies under the Letter Agreement
shall have the effect of impairing or releasing Guarantor's obligations and
liabilities to Upper Mill, or of waiving any of Upper Mill's rights and remedies
under this Guaranty or otherwise. Any partial exercise of any rights and
remedies granted to Upper Mill shall, furthermore, not constitute a waiver of
any of Upper Mill's other rights and remedies; it being Guarantor's intent and
agreement that Upper Mill's rights and remedies shall be cumulative in nature. A
waiver or forbearance on the part of Upper Mill as to one event of default shall
not constitute a waiver or forbearance as to any other default.

         WAIVER OF JURY TRIAL. GUARANTOR HEREBY KNOWINGLY AND IRREVOCABLY WAIVES
TRIAL BY JURY IN ANY ACTION OR PROCEEDING TO ENFORCE, OR OTHERWISE INVOLVING,
THIS GUARANTY. GUARANTOR FURTHER

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IRREVOCABLY CONSENTS TO THE JURISDICTION AND VENUE OF ANY STATE OR FEDERAL COURT
SITTING IN OR FOR NORTHAMPTON COUNTY, PENNSYLVANIA.

         FULL KNOWLEDGE. Guarantor has had the opportunity to discuss this
Guaranty, and all waivers, consents, agreements and covenants herein contained,
with counsel of her own choosing, and Guarantor understands the significance and
the consequences thereof, and acknowledges the reasonableness of the same.

         ATTORNEYS' FEES/COSTS. The Guarantor shall pay Upper Mill's reasonable
attorneys' fees and all costs and other expenses incurred in enforcing this
Guaranty against the Guarantor.

         MISCELLANEOUS PROVISIONS.  The following miscellaneous provisions are
a part of this Guaranty:

                 Amendment. No amendment, modification, consent or waiver of any
provision of this Guaranty, and no consent to any departure by Guarantor
therefrom, shall be effective unless the same shall be in writing signed by a
duly authorized officer of Upper Mill, and then shall be effective only as to
the specific instance and for the specific purpose for which given.

                 Caption  Headings.  Caption  headings  of the  sections  of  
this  Guaranty  are  for  convenience
purposes only and are not to be used to interpret or to define the provisions 
hereof.

                 Gender and Form. In this Guaranty, whenever the context so
requires, the reference to any gender applies to all genders, and the singular
includes the plural and the plural includes the singular.

                 Governing  Law.  This Guaranty  shall be governed and 
construed in accordance with the law of the Commonwealth of Pennsylvania.

                 Notices. All notices, demands and communications provided for
herein or made hereunder shall be effective when delivered in person, or three
days after being sent via certified mail, return receipt requested, or on the
day after being sent via overnight courier requiring a signature for delivery,
or, if sent via facsimile, provided notice is also given by another approved
means, when such confirmation notice is effective, addressed in each case as
follows, until some other address shall have been designated in a written notice
to the other parties hereto in like manner.

         If to Upper Mill:                           Upper Mill, L.P.
                                                     99 South Cameron Street
                                                     Harrisburg, PA  17101
                                                     Attn:  William I. Roberts

        

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If to Jennifer Barclay                      Jennifer Barclay
                                            c/o Blue Fish Clothing, Inc.
                                            No. 3 Sixth Street
                                            Frenchtown, NJ  08825

                 Severability. If any provision of this Guaranty is held to be
illegal, invalid or unenforceable under present or future laws during the
effectiveness of this Guaranty, such provision shall be fully severable; and,
this Guaranty shall be construed and enforceable as if the illegal, invalid or
unenforceable provision had never comprised a part of it, and the remaining
provisions of this Guaranty shall remain in full force and effect and shall not
be affected by the illegal, invalid or unenforceable provision or by its
severance herefrom. Further, in lieu of such illegal, invalid or unenforceable
provision, there shall be added automatically as a part of this Guaranty, a
provision as similar in terms to such illegal, invalid or unenforceable
provision as may be possible and legal, valid and enforceable.

                 Successors and Assigns. This Guaranty shall inure to the
benefit of, and be enforceable by, Upper Mill and its successors and assigns,
and shall be binding on, and enforceable against, Guarantor and Guarantor's
heirs, representatives, successors and assigns.

         IN WITNESS WHEREOF, Guarantor has caused this Guaranty to be executed
as of the day and year first above written.

                                               GUARANTOR:

                                               /s/ Jennifer Barclay
                                               --------------------
                                               Jennifer Barclay