Subseries consists of chiefly of Osler's correspondence collected by Cushing relating to the period between 1886 to 1904, during which time Osler was in Philadelphia and then Baltimore. Correspondence includes both original letters and transcriptions of letters. In addition to correspondence are some accompanying notes (both by Cushing and by Osler), clippings, articles, and other ephemera related to Osler.

Subseries consists of chiefly of Osler's correspondence collected by Cushing beginning in 1905 with Osler's appointment at Oxford University until his death in 1919. Correspondence includes both original letters and transcriptions of letters. In addition to correspondence are some accompanying notes (both by Cushing and by Osler), clippings, articles, and other ephemera related to Osler.

Subseries consists of chiefly of correspondence but also includes some accompanying notes, clippings, articles, and other ephemera related to Osler's childhood and early career period in Montreal.

Sub-series A-1 contains experiment notebooks from the Chemistry Laboratory, Cambridge, concerning the study of stereochemistry. Of special relevance are the experiments pertaining to the optical activity caused by the restriction of the rotation of a trivalent nitrogen atom. It includes material produced at the Sir William Dunn Institute of Biochemistry related to oxidation reduction systems with particular relevance to the reduction of glutathione and the study of peroxidases in milk and horseradishes. This sub-series is comprised of 4 files (files no. 1 to 4), which are arranged chronologically.

Subseries contains a copy of Dr. Arthur Vineberg's thesis on the mechanism of gastric secretion, presented in partial fulfillment of the requirements for the Degree of Doctor of philosophy(physiology) at McGill University in September 1933.

Miscellaneous photographs of brain of [a patient] and series of X-rays on “Bone Transplantations (Free Bone Grafts).

Consists of the records of deceased patients who were only consulted between 1926 and 1939.

This sub-series consists of illustrations and photographs which were included as part of a number of Dr. Penfield's published writings. Each of the series' file numbers (ex. W/PV XX) correspond to the published writing file in which the images were used (ex. W/P XX).

Sub-series C-2 consists of manuscripts, typed copies and printed versions of unpublished articles written or co-authored by Dr. Cone. It also includes manuscripts and typescripts forwarded to Dr. Cone by others to be edited. This sub-series is comprised of 22 files (files no. 193 to 214).

Sub-series C-1 consists of manuscripts, typed copies and printed versions of published articles written or co-authored by Dr. Cone. In some case only printed copies exist. This sub-series is comprised of 23 files (files no. 170 to 192).