Index Catalog // ScholarsArchive@OSU

Creator:: Warner, Roderick Ward
Abstract:: The diel fluctuations in the abundance of alfalfa weevils, as measured by sweeping, were studied during 1972 and 1973 in three of the four major alfalfa growing regions of Oregon. It was found that in all regions studied significantly more new generation adults could be captured after dark than during...
Resource Type:: Masters Thesis
Full Text:: privacy P. 0. Ritcher The diel fluctuations in the abundance of alfalfa weevils, as measured by

Creator:: Hartman, Margaret Jane, 1943-
Abstract:: Two organophosphates (Ruelene and Tiguvon) and two carbamates (Sevin and Baygon) were administered topically at various sublethal concentrations to cricket eggs. All the pesticides caused an immediate decrease in the acetylcholinesterase (AChE) activity level in the embryo, but the level usually returned to normal within three days after dosage. The...
Resource Type:: Dissertation
Full Text:: THOPp-m D A. rl VT T TTIAV1 Redacted for Privacy Abstract approved: P. 0. Ritcher Two

Creator:: Carlson, David Craig
Abstract:: The genus Ochodaeus Serville contains approximately sixty species and is World wide in its distribution. One-half of these species are known from the Nearctic and Neotropic regions. Adults of six previously described species common to the United States have been studied in detail. The mandibles, stridulatory peg, and male genitalia...
Resource Type:: Masters Thesis
Full Text:: , institutions, and private collections. Field collecting by the writer and Dr. P. O. Ritcher took place during

Creator:: Carlson, David Craig
Abstract:: The genus Lichnanthe Burmeister contains eight extant and one fossil species which are strictly nearctic in distribution. The subfamily Glaphyrinae, however, is distributed nearly world-wide. Five species were previously described and three are described as new herein. All eight extant species are described in detail herein, synonomies are made current,...
Resource Type:: Dissertation
Full Text:: ) Abstract approved: Redacted for Privacy Dr. P. 0. Ritcher The genus Lichnanthe Burmeister contains eight

Creator:: Wold, Janet Lee
Abstract:: Rhyacophila is one of the largest genera of caddisflies, containing about 465 species. Approximately 100 species are found in North America with 83 occurring in the west, The larvae of 24 western North American species are associated for the first time, making a total of 38 species for which larvae...
Resource Type:: Masters Thesis

Creator:: Davidson, Jean Hoyt Puckle
Abstract:: The genus Coenonycha contains 30 described species of small to medium sized scarabs. They are found in the arid and semi-arid regions of western United States and northern Baja California. The adults feed at night on several genera of xerophylous plants. An examination of the male genitalia of the 19...
Resource Type:: Masters Thesis
Full Text:: Dr. P. 0. Ritcher, Oregon State University, Corvallis, Oregon; Dr. R. 0. Schuster, University of

Creator:: Davidson, Jerry Mitchell
Abstract:: The male genitalia of 69 species, representing eight genera of sphecid wasps, were examined in order to ascertain their taxonomic value. In all, the male genitalia of approximately 1000 specimens were critically studied. Emphasis was placed on the genitalia and associated sclerites of the known males in the genus Eucerceris....
Resource Type:: Masters Thesis
Full Text:: Paul O. Ritcher The male genitalia of 69 species, representing eight genera of sphecid wasps, were

ScholarsArchive@OSU