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EXHIBIT 23.1
CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS
We consent to the reference to our firm under the caption "Experts" in
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.
Palo Alto, California
October 25, 2000
