THE COTTON LEAF PERFORATOR, Buc culatrix thurberiella Busck, a pest of cotton native to the southwestern United States, is apparently restricted in its feeding to wild and cultivated species of Gossypium. In the past this tiny insect has been the cause of severe damage to commercial cotton in the desert areas of California and was one of the reasons for the cessation of cotton production in southern California in the 1930's. It was not until the introduction of the chlorinated hydrocarbon insecticides in 1946-48 that cotton production was resumed in these areas.

Photographs were provided by R. S. Rejesus, Department of Entomology, U.C. Riverside. This research was conducted with financial support from the California cotton industry, and with the cooperation of many individual growers.