American amateur naturalist with a particular interest in lichens. William Calkins worked in business and law and was a keen writer, publishing over 150 titles covering broad aspects of geology, zoology, botany, history and war correspondence. Living in Illinois for his entire life Calkins began by teaching as a ward principal in Ottawa, IL (1862), but gave up this role at the onset of the Civil War when he enlisted and served until its close. As a naturalist Calkins initially took an interest in rocks and fossils but when his large collection was destroyed in the Chicago fire of 1871 he turned his attention to shells and seed plants, developing a phanerogamic herbarium of some 4,000 specimens.

In 1885 Calkins first took up the study of mycology and became particular interested in lichens, collecting specimens in Florida and Illinois which he sent to William Nylander for study. Within his collection Nylander identified and described between 25 and 30 new species and Calkins published several papers in this field too. Some of his most important contributions to the botanical literature include "The lichen-flora of Florida" (1887), "The lichen-flora of Chicago and vicinity" (1896) and "Mosses of Cook County, Illinois" (1910).

Sources:
B. Fink, 1915, "William Wirt Calkins, amateur mycologist", Mycologia, 7(2): 57-60
F.A. Stafleu and R.S. Cowan, 1976-1998, Taxonomic Literature, 2nd edition (TL-2).