An Apparent Correlation between the Feeding Habits of Certain Pteromalids and the Condition of Their Ovarian Follicles1 (Pteromalidae, Hymenoptera)

Abstract

During the past two years the Citrus Experiment Station, in cooperation with the Bureau of Entomology of the United States Department of Agriculture, has introduced into California from Europe several species of Hymenoptera parasitic on the alfalfa weevil, Phytonomus variabilis. Chamberlin (1924) lists eight important species. These are able to live under a rather large range of climatic conditions and most of them have at some time been introduced and colonized in the Rocky Mountain region of the United States. Only two species are known to be established, although the introduction work began twenty-three years ago.