1919] Hine: Genus Erax 113 



of the anterior branch always present. The females are easily associated 

 with the males, but have no very good characters for distinguishing 

 them from others of the same sex. The wings are hyaline in armatus, 

 at least the yellowish tinge is hardly evident. The tibia of the male 

 shows an apgular prominence posteriorly, somewhat nearer its base 

 than its apex, the female has the first five abdominal segments rather 

 densely gray pollinose, with rounded black spots above on two, three, 

 four and five ; segment six is nearly all black above and seven is entirely 

 black. Femora, tarsi and apexes of tibiae black, basal three-fourths or 

 more of each tibia pale yellow. Total length 30 to 32 millimeters. 



Ten specimens from Davis Mountains (F. M. Gaige) 

 Cotulla (F. C. Pratt) and Uvalde, Texas. Taken in June and 



July. 



Erax sagax Williston. 



Total length 25 to 27 millimeters. Wing wide and conspicuously 

 light brown all over in both sexes; male with the hind tibia suddenly 

 enlarged beyond the middle of its length; both sexes with silvery 

 markings on the abdomen. In the male, segments two and three are 

 narrowly silvery on the sides, four, five and six are largely silvery, but 

 four has a rather large black triangular spot above and five has a narrow 

 black marking above anteriorly, six entirely silvery, seven black above 

 with narrow sides silvery. 



Female with segments two, three, four and five silvery at the sides; 

 this color is extended dorsally on the hind margin of three and on the 

 whole of four and five, but in no case does it meet above so there is a 

 conspicuous black space left dorsally on each segment; six and seven 

 nearly entirely black. The femora are red apically in both sexes, and 

 posteriorly in the female, in the specimens at hand. 



Three specimens from Guadalajara, Mexico, June 24, 1903, 

 collected by McClendon. 



Erax tagax Williston. 



Total length 28 to 30 millimeters. Wing ver}^ pale brownish. 

 Male hind tibia with a distinct prominence posteriorly near distal third 

 and a conspicuous patch of black pile anteriorly just opposite and 

 extending to apex. Abdominal segments of the male two, three, four 

 and five black with narrow sides and posterior margin silvery white 

 pollinose, six wholly silvery, seven mostly silvery, but with posterior 

 margin above dark. Female, segments two, three, four, five and six 

 black, with sides and narrow posterior margin white pollinose, seven 

 black, oviduct black not much longer than abdominal segments six and 

 seven. Femora black in the male and mostly redish posteriorly in 

 the female in the specimens at hand. 



A dozen specimens from Arizona. 



