188 ERNEST A. BACK. 



cf . — Length 20 mm. — -Black, wings of the same color; face, front and 

 occiput wholly white pruinose; the thoracic dorsum in most specimens 

 reddish-yellow, with a large central area black, in others wholly pitchy 

 black or black; pleura, pectus and scutellum always black. Abdomen 

 reddish-yellow; the first and second segments, except the posterior 

 margin of the latter, the "semi-ovate lateral spots" of the following 

 segments, the entire venter and hypopygium black; the posterior 

 lateral margins of segments 2-5 white pruinose. Clothing of entire 

 body black, except the yellowish-red hair on the reddish portion of 

 the tergum of the abdomen. Legs black; tibiae and tarsi pitchy 

 black, alinost a dark testaceous. Wings black, larger and broader 

 than in abdominalis. 



Type. — M. C. Z. Three male specimens without locaHty 

 label and in rather poor condition. 



Habitat. — Pecos River; Western Tex,; N. M. 



The conclusion from Loew's description that there are black 

 spots on the sides of the abdominal segments is in a sense 

 misleading. Separate spots, there are none. The black on 

 the sides of the segments, as I find by examining the type 

 material, is only an encroachment of the black of the venter 

 upon the sides of the segment. The same is found in eutrophus, 

 only there the black encroaches evenly, while in rhadamanthus 

 the black extends upward to a greater extent in the middle 

 than elsewhere — hence Loew's " maculis lateralibus singulorum 

 semiovatis nigris, angulos posticos non attingentibus." For 

 some unaccountable reason, Loew did not embody a descrip- 

 tion of the white pruinose spots on the posterior lateral angles 

 of segments. 



OsprioceriLS ventralis. 



Ospriocerus ventralis Coquillett, Ent. News, IX, 37, 1898. 

 Ospriocerus ventralis Howard, Insect Book, 1902, PI. XIX, fig. 14. 

 ^ 9 . — Length 20-23 mm. — Venter largely yellow, the entire abdomen 

 yellow, except the first segment, base of the second, and the genetalia, 

 which are black; in the female the apex and sometimes the under side 

 of the last segment is black. Pulvilli and bases of the tarsal claws, 

 yellowish; all the hairs and bristles black, except the short hairs of the 

 abdomen, which are chiefly yellow. Wings blackish, with steel-blue 

 reflections. 



Type.—V. S. N. M. Cat. No. 4253. The type consists of 

 three males and two feinales. 



Habitat. — Arizona (type); Car Canyon, Huachuca Mts., 

 Cochise Co. (Aug., H. Skinner), Ariz. 



