Body above pale yellow, abdomen with faint brown mid-dorsal and dorso-lateral spots; a vinous stripe in front of wing-base; body beneath and legs whitish buff. Wings above yellow, paler distally on fore wing and costally on hind wing. Fore wing with faint indications of an arcuate, blackish-fuscous, broken antemedial band; orbicular represented bv a black dot in cell; reniform obsolete; postmedial line strongly zig-zagged, inierrupted at veins, preceded by black dashes in cells M2, to Cu2; a subterminal row of brownish-fuscous spots between veins; fringe yellow; hind wing with interrupted, zig-zagged postmedial line, preceded by black dashes, as on fore wing; subterminal spots stronger than on fore wing; fringe yellow. Wings beneath whitish buff; costa of fore wing weakly infuscated; a fuscous dot-like orbicular and lunate reniform; no other markings. Expanse 67 mm.

Of the many species of fleas incriminated in plague transmission, the most notorious is the oriental rat flea, Xenopsylla cheopis (Rothsch.). This is due to its early discovery as a plague vector (Simond, 1898), its demonstrated superior ability to transmit the infection (Kartman and Prince, 1956), and its recognition as the principal vector of plague from rat to man. Holland (1949) regards its presence in any geographical area as a matter of concern.

The two species described below live in the burrows of the common prairie dog.

Saprinus cynomysi n. sp.

Length (apex of thorax to apex of suture) 6-6.2 mm.; width 5 mm. Black, strongly shining throughout.

Head moderately finely and sparsely punctate, the punctures becoming very fine and sparse at middle of occiput. Supraocular stria distinct, extending across the front.

A convenient and efficient method of determining if qualitative changes are associated with changes in density of insect populations is to search for changes in isozyme frequencies (Stock and Guenther 1979). However, obtaining sufficient material for analysis of low density populations presents a problem. We have found that the use of sticky traps baited with synthetic pheromone is an efficient and practical method of surmounting this problem.

Approximately 75 species of Artemisia, or sage, occur in the Rocky Mountain region, many of these being infested by aphids, often to a considerable extent. The great economic importance of several specis of Artemisia as food for range livestock and the incomplete knowledge of the aphids attacking them in Utahled the writers to undertake this study. Most of the report deals with the apterous forms which are most frequently encountered and which possess good specific characters for identification.

Attention is called to some characters used by the writer. The dorso-central bristles are numbered from the anterior edge of the mesonotum designating the bristle in front of the transverse suture as the first dorso-central. Hering (1927) numbers them in the reverse direction calling the bristle in front of the transverse suture the fourth dorso-central. Previous papers on the chaetotaxy of Diptera have not numbered the dorso-central bristles. The number and arrangement of the setae along the lower and hind margin of the cheeks also lend good characters. The writer speaks of the cheeks collectively as the portion between the eyes and the mouth including the gena or wangen arrd the bucca. The term occiput has been used to designate the whole of the back of the head. The color of the occiput has been found valuable especially when the yellow of the cheeks continues back of the eye. In some cases the yellow of the cheeks is interrupted near the vertex by the black of the occiput.

A distinctive new species of Austromenopon from two species of shearwaters, Puffinus kuhlii (Scopoli) and Puffinus leucomelas (Temminick), is described herein. The new species is based on specimens collected from museum study skins and also from material lent to me by Dr. Theresa Clay, British Museum (Natural History) and the U.S. National Museum. I am indebted to Dr. Clay for the opportunity to examine material from the Meinertzhagen collection and to Dr. K. C. Emerson for reviewing this manuscript.

Betulaphis viridis is described and illustrated. It is a bright green species that occurs on the upper surfaces of the leaves of Betula pendula Roth and is known only from Ontario.

Grasshopper density and species composition were determined from 1982 to 1985 in four 75-ha pastures in the northern mixed prairie region near Miles City, MT. Treatment in two pastures consisted of sagebrush removal and interseeding alfalfa and cicer milkvetch. Two pastures were not treated. The treated pastures were grazed only half as long as the untreated pastures but with twice the number of steers. Forage yield decreased in all pastures from 1983 to 1985 because of below-average precipitation and grasshopper density increases. In one pasture, 10% of the legume seedlings were destroyed by grasshoppers. The annual rates of increase in total grasshopper presence were similar in treated and untreated pastures. However, Melanoplus sanguinipes (F.), which eats forbs and is a strong flyer, increased more in treated than untreated pastures; six additional abundant species, all of which were grass feeders, did not increase more in treated pastures. Thus, treatments did not markedly affect total grasshopper population trends but did influence species composition and provided additional food plants for some species.