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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 StemCells, Inc. for
the registration of 15,000,000 shares of its common stock and to the
incorporation by reference therein of our report dated February 12, 2002, with
respect to the consolidated financial statements of StemCells, Inc. included in
its Annual Report (Form 10-K) for the year ended December 31, 2001, filed with
the Securities and Exchange Commission.

                                        /s/ Ernst & Young LLP

Palo Alto, California
June 26, 2002

