204 THE CANADIAN ENTOMOLOGIST 



terminal segment, one a little below the apex." The sketch sup- 

 plied by Mr. Johnson indicates that the first of the flagellar seg- 

 ments has two of these weak segments, the next two have three 

 each while the short terminal segment is not further divided, 

 these totalling up to the nine distinct segments in C. primitiva. It 

 will be seen from the figures (fig. 3) that the flagellar segments 

 in Pterochionea are all short-cylindrical; in C. primitiva (fig. 4) 

 the basal segments are short with short verticils, these segments 

 gradually becoming more attenuated and provided with longer 

 bristles, the last segment shorter with three terminal bristles. 



The male hypopygia of Chionea and Pterochionea show a 

 peculiar, powerful type of genitalia, consisting of. a massive pleurite 

 and a single elongate pleural appendage (figs. 1, 2). In Crypteria 

 the appendages are small, tM^o in number and quite normal. Thus 

 in the structure of the antennae, Chionea comes closest to Cryp- 

 teria, but in the hypopygium the condition is remarkably close to 

 Pterochionea. There can be little doubt but that these two genera, 

 with perhaps others yet to be discovered, are the direct ancestors 

 of our familiar snow-flies, Chionea. As stated in another paper, 

 this interpretation will place the group at the very end of the 

 eriopterine series. 



Chionea primitiva, sp. n. 



Size large; form stout; entire body hairy; head elongated; 

 antennae with nine flagellar segments beyond the fusion segment. 



Male. — Length 5.8 mm.; diameter across thorax, 1.5 mm. 



Mouth parts yellowish brown; palpi dark brown. Antennae 

 elongate, the scapal segments yellowish brown, the flagellum 

 darker; first segment of the scape a little broader basally, with a 

 group of long bristles on the outer face; second segment narrowed, 

 basally enlarged, darkened and provided with bristles beyond the 

 basal portion; fusion-segment of the flagellum conical, with short 

 verticils; it is shorter than the second segment of the scape but 

 longer than the following segment of the flagellum; beyond the 

 fusion-segment are nine distinct segments, increasing in length 

 toward the tip of the organ, the verticils also increasing in length 

 from the base outward, those of the first four segments shorter 

 than the segments that bear them, the others very long, longer 

 than the segments that bear them; the terminal segment is smaller, 



