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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. 2 to the Registration Statement (Form S-3 No. 333-49020)
and related Prospectus of Cygnus, Inc. for the registration of shares of its
common stock for the maximum aggregate offering price of $33 million and to
the incorporation by reference therein of our report dated January 28, 2000,
with respect to the 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
December 22, 2000
