From the Introduction by Theodora Kroeber, Editor: The number of documents having to do with Ishi is finite. For the reader who wishes to know something of the sources from which the story flows, there are reproduced here the principal out-of-print and most inaccessible primary materials on Ishi and the Yahi Indians.   Of first importance are monographs on Ishi, his people, his languages, his medical history, whose authors are Professors Thomas T. Waterman, Alfred L. Kroeber, Edward Sapir, and Saxton T. Pope, M.D. Most of these monographs are here reprinted in full. Next in interest and importance are the books of reminiscences concerning the Yahi Indians written by white settlers in or adjacent to Yahi country in the years following closely upon the gold rush. These are usually in small editions, long out of print. Two, those written by Carson and R. A. Anderson, are reprinted in full; the others, only those parts having to do with Ishi and the Yahi. There are letters bearing on our subject, newspaper accounts, and pictures, of which we include significant examples. There are as well books and articles having to do only in part with Ishi and his people. We reprint only those parts.    Beyond these essential primary materials, the editors made hard choices to keep the number of pages realistic. Readers with areas of special interest will regret some of our exclusions among the secondary but often fascinating accounts: of archaeological findings in the Yahi homel∧ of linguistic quirks and grammatical technicalities--a large literature, difficult for the uninitiate; of medical history when it adds nothing to our understanding of the man Ishi.   Our order of presentation is chronological, beginning with the background materials, then going to Ishi's first entry into the outside world, then to his years at the museum, and, finally, to his death.   We have not included the occasional newspaper stories of still-living Yahi Indians supposed to have been seen or heard in the Yahi hills and caves after Ishi's departure, since none were ever substantiated. When in 1914 Ishi returned to his old home for a few weeks with Waterman, Kroeber, Pope, and Pope's son, Saxton, Jr., he found the land, the caves, and the village sites as he had left them.