Published online by Cambridge University Press: 31 May 2012
In 1934, Knowlton and Rowe (2) recorded five species of Simuliidae from Utah, including Simulium (Simulium) vittatum Zett., and four species described as new: namely, S. (S.) brevicercum, S. (S.) nigresceum, S. (Eusimulium) pilosum, and S. (E.) utahense. In May and October, 1937, G. F. Knowlton kindly forwarded to me for examination about seven hundred specimens of blackflies collected in various parts of Utah and Idaho. A study of this material showed that nine described species and six species new to science were represented. The distribution records and descriptions of the new species are given in the following pages.