One of the earliest books in the Franclemont Collection is this 1796 work on insect classification by Johann Christian Fabricius (1745-1808), a Danish student of Linnaeus and professor of natural history, finance and economics in Kiel, Germany. In contrast to Linneaeus’s insect classification system based on wings, Fabricius established an insect taxonomic system based on mouthparts, which he believed to be the mark of the most natural genera since their characteristics stemmed from the diet of each insect and their biology is dependent on their diet.

Although Fabricius considered systematics more important than a dry description of the various species, his contributions to taxonomy are imposing: he named and described at least 10,000 insects.