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                                                                    EXHIBIT 23.1
 
              CONSENT OF ERNST & YOUNG, LLP, INDEPENDENT AUDITORS
 
     We consent to the reference to our firm under the captions "Selected
Financial Data" and "Experts" and to the use of our report dated April 3, 1996
(except Note 7, as to which the date is July 24, 1996), in the Registration
Statement (Form S-1) and related Prospectus of Cerus Corporation
for the registration of shares of its common stock.
 
                                          ERNST & YOUNG LLP
 
Walnut Creek, CA
 
     The foregoing consent is in the form that will be signed upon the
completion of the stock split and reincorporation in Delaware described in Note
7 to the financial statements.
 
                                          /s/  ERNST & YOUNG LLP







 
Walnut Creek, CA
September 3, 1996

