The Leo Loeb papers consist of Dr. Loeb’s note books, lectures, research notes and manuscripts, and scrapbooks. The series of personal correspondence is largely incoming and fragmentary with some letters filed in Series 8: Bibliographical notes on the medical literature, manuscripts, research pathology data and occasional related correspondence, Undated & 1921-1958. The papers also include notes and drafts for two unpublished books. One is on mental processes and titled _Psychical Goods_or _The Imponderables. _The other unfinished book is on cancer.