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EXHIBIT 23.1
CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITOR
We consent to the reference to our firm under the caption "Experts"
in the Amendment No. 1 to the Registration Statement (Form S-3) and related
Prospectus of Cygnus, Inc. for the registration of shares of its common stock
for the maximum aggregate offering price of $36 million and to the
incorporation by reference therein of our report dated January 28, 2000, with
respect to the consolidated financial statements of Cygnus, Inc. included in
its Annual Report (Form 10-K) for the year ended December 31, 1999, filed
with the Securities and Exchange Commission.
/s/ ERNST & YOUNG LLP
Palo Alto, California
November 10, 2000
