THE BEES OF ALBERTA—IV

Female. Length about 7 mm., anterior wing 6.5 ; robust, without much hair, the abdomen bare and shining, without hair bands, but the mesopleura with rather abundant greyish-white hair; head and thorax dark green, the thorax posteriorly and at its sides almost black; mandibles black, faintly reddish apically; margin of clypeus black; face shining green; mesothorax dark, more bluish green, dull in front, shining posteriorly; scutellum steel-blue, postscutellum black, but metathorax, seen from above, olive green; legs and abdomen black; antennae black; tegulae dark brown, with minute punctures, only seen under microscope; clypeus flattened in middle, with several longitudinal grooves; front dull; vertex shining blue; mesothorax without distinct sculpture as seen under a lens, but with minute rather sparse punctures on a minutely lineolate surface; scutellum strongly bigibbous, the elevations shining; area of metathorax large, dull, with a shining margin, plications strong on basal half; posterior truncation sharply bounded; wings conspicuously reddish, stigma and nervures dull red ; second cubital cell large, receiving recurrent nervure near end; hair on inner side of hind tarsi pale reddish; hind spur with four very long oblique spines, and a fifth rudimentary one; abdomen without evident punctures, as seen under lens, the microscope shows excessively minute scattered ones.