PSYCHE 
VOL. XXXI. JUNE-AUGUST 1924 Nos. 3-4 
NORTH ‘AMERICAN SPECIES OF THE SUBGENERA 
OPACIFRONS DUDA AND PTEREMIS RONDANI 
OF THE GENUS LEPTOCERA OLIVIER^ 
(DIPTERA, BORBORID.E) 
By Anthony Spuler. 
Pullman, Washington. 
Introduction. 
The subgenus Opacifrons Duda is comparatively small 
and contains but a few North American species. In none of the 
species are the individuals abundant. Some of the species are 
represented by a single or a few specimens. 
The subgenus Pteremis Rondani is represented by but three 
North American species. The characters in this subgenus are 
so striking that there is a question whether Pteremis should be 
classed as a subgenus as Dr. 0. Duda has done, or whether 
it should be classed as a genus as was done by Rondani. 
This paper is one of a series of papers on the North American 
species of the Family Borboridse. 
Opacifrons Duda. 
Duda: Abahnd. Zool-botan. Ges. Wien., X. I. 28 (1918). 
Frontal triangle opaque; preapical bristle usually absent; 
apical bristle always absent; hind tibia? uniformly short hairy; 
first section of costa more or less densely short hairy ; last section 
of third vein straight or gently curved like letter S; usually not 
more than three pairs of dorsocentral bristles, the anterior pair 
not convergent; posthumeral bristles usually absent; scutellum 
with four marginal bristles. 
Genotype. — 0. coxata Stenh. by present designation. 
Contribution from the Division of Entomology of the Agricultural 
Experiment Station, State College of Washington. 
