Exhibit 23.1 CONSENT OF INDEPENDENT AUDITORS We consent to the use of our report dated April 14, 2000, included in the Annual Report on Form 10-K of StemCells, Inc. (formerly CytoTherapeutics, Inc.) for the year ended December 31, 1999, with respect to the consolidated financial statements, as amended, included in this Form 10-K/A. /s/ Ernst & Young LLP Providence, Rhode Island December 1, 2000