The Henry Chandler Cowles photograph collection is comprised primarily of lantern slides. As a botany professor at the University of Chicago, Cowles led several field trips to observe ecological environments during the years from 1898 to 1934. The lantern slides in this collection cover the geographic areas of Michigan, Colorado, Indiana, Wisconsin, and Illinois and include photographic subjects such as dunes, plant life, forests, landscapes, and class group pictures.
The Henry Chandler Cowles photograph collection is comprised primarily of glass lantern slides from Cowles's ecology trips covering the years 1898 to 1936 with the majority being unmarked or falling between the years 1900-1912. Captions affixed to the plates are noted when available along with any numbering. Some of the handwriting is difficult to make out as are the Latin names of the plants but every attempt at correct spelling has been made. The collection is divided into seven series: Michigan Photographs, Colorado Photographs, Illinois Photographs, Indiana Photographs, Wisconsin Photographs, Miscellaneous Photographs, and Indiana Transparencies. Each state has subseries of General -- which indicates a many single location photographs -- and subseries of cities for which a group of photographs exists.