Exhibit 23.1



                       Consent of Independent Auditors

We consent to the incorporation by reference in the Registration Statement 
(Form S-8 No. 33-49524 and 333-29335) pertaining to the 1998 Incentive Stock 
Plan, 1992 Equity Incentive Plan, 1992 Employee Stock Purchase Plan and 1992 
Stock Option Plan for Non-Employee Directors, in the Registration Statement 
(Form S-8 No. 333-10773) pertaining to the 1992 Equity Incentive Plan, in the 
Registration Statement (Form S-8 No. 333-37313) pertaining to the 1996 
StemCells, Inc. Stock Option Plan and the 1997 CytoTherapeutics, Inc. 
StemCells Research Stock Option Plan and in the Registration Statements 
(Form S-3 No. 33-68900 and No. 333-91228) of CytoTherapeutics, Inc. and in the
related Prospectuses of our report dated February 12, 1999, with respect to 
the consolidated financial statements and schedule included in the Annual 
Report (Form 10-K) of CytoTherapeutics, Inc. for the year ended December 31, 
1998.

                                                              Ernst & Young LLP


Boston, Massachusetts
March 29, 1999