This early American naturalist was one of the first to stress field observations and biology of insects, illustrating the stages seen, while studying their classification. He was known to have been preparing a general work on American insects, the first parts of which, text and figures, were shipped to, and acknowledged by Thomas Horsfield in London just before Cist's death. The final disposition of that manuscript is now unknown. The notes and drawings herein described are assumed to be a part of the same study.

The six field notebooks contain introductory comments on entomology, descriptions of various groups of insects, followed by the observations on forms, characteristics and life histories of individual species. This work was to appear under the title of “Entomologia Americana, or the Insects of the United States from Georgia to Maine.” The entries number 761 but those for 462 to 549 and 631 to 699 are lacking.

The series of 165 watercolor drawings and 36 pencilled sketches is contained in 38 folders. In some cases there are descriptive notes. Most of the species figured are named, with the numbers corresponding to those used in the notebooks cited above.