1919] Hine: Genus Erax 143 



both above and beneath; thir,d segment with a pecuhar band of long 

 hair, silvery above and darker beneath, extending entirely around it 

 and parted on the mid-dorsum and also on the mid-venter and in each 

 case directed outward; the hairs on the anterior part of the segment 

 are directed somewhat backward and those on the posterior are directed 

 forward to about the same extent ; narrow posterior margin of the third 

 segment and segments four to seven inclusive with but very little pile 

 but conspicuously silvery pollinose. Hypopygium black and almost 

 entirely black pilose, but with a little yellow pile basally and also 

 apically;- black pile especially long and prominent on sides and venter; 

 dorsally of nearly uniform width, but wider and shorter than in sagax; 

 from side view a very prominent extension at apex. Figure 42. 



Male type from Morelos, Mexico, collected by D. C. Craw- 

 ford, in the author's collection. 



The peculiar third abdominal segment and the hypopygium 

 characterize this species. 



Erax splendens Williston. 



Total length 22 to 25 millimeters. Mystax and beard bright 

 yellow, hair and bristles of the front and the occipito-orbital bristles 

 black, thorax rather sparsely brown pollinose and with black hair, 

 wings yellowish, furcation of the third vein not far from the anterior 

 cross vein, stump a little longer than the basal section. Front legs 

 with dense yellow hair anteriorly on coxas, and ventrally on femora, 

 tibicB and tarsi, but there is much black hair on the appendages also; 

 middle ahd hind legs mostly black haired, but there is some variation 

 in a series of specimens. Legs entirely shining black in ground color. 

 Male abdomen black with black vestiture, except segments four, five 

 and six, which are silvery. See Figure 39. Female, abdomen dark, 

 segments two to six inclusive yellowish gray pollinose with rather small 

 irregular markings dorsally. Oviduct shining black, hardly as long as 

 the last three abdominal segments. 



Several specimens of both sexes from Guadalajara, Mexico, 

 collected by McClendon. 



The very dark color of the body of this species with the 

 bright yellow mystax and beard makes its identification easy. 



Erax truncatus Hine. 



Thorax yellowish-brown, above, abdomen gray, first four segments 

 with long white hairs, legs black with the exception of the basal part of 

 each tibia which is light reddish. Total length 22 to 30 millimeters. 



Mystax and beard white, ocellar, occipito-orbital and a transverse 

 row of bristles on the dorsum of the prothorax black, palpi with black 

 and white hairs intermixed, dorsum of the thorax and the scutellum 

 with many black hairs and bristles, but there are some white ones 

 intermixed, wings hyaline. 



