24 Mr. T. I). A. Cockerell — Descriptions and 



Halictoides mulleri, Ckll., 1898. 



This species was described from a single female. At Pasa- 

 dena, California, April 8, 1909, Mr. Grinnell caught an 

 insect which must be itsmale, having all tbeessential characters 

 of the species, including the strongly bluish vertex, the broad 

 head, &c. It is remarkable for the hind legs, of which the 

 femora and tibia? are greatly swollen (the latter also curved), 

 while the flattened shining basitarsus is exceedingly short 

 atid broad, and broadly truncate apically. The flagellum is 

 quite thick, with the apical two-thirds ribbed beneath. 



Uesperapis semirudis, sp. n. 



? . — Length about 10| mm. 



Black, with dense entire creamy-white hair-bands on the 

 apical margins of the abdominal segments ; hair ol head and 

 thorax rather dull white, long and black on vertex; meso- 

 thorax and scutelluiu with short greyish hairs, giving a 

 dusty effect, around their margins, and scanty erect black hairs 

 on the dixk ; face (and especially vertex) shining, but rneso- 

 thorax, scutellum, and large basal area of metathorax dull 

 and minutely roughened ; flagellum stout, dull reddish 

 beneath ; tegulse blackish anteriorly, hyaline testaceous 

 posteriorly. Wings du*ky hyaline, stigma dull ferruginous, 

 nervures fuscous ; b. n. falling some distance short of t.-m. ; 

 second s.m. long, narrowed more than half to marginal, 

 receiving first r. n. a trifle nearer base than second to apex ; 

 third discoidal cell with its apical angle much less than a 

 right angle. Legs black, ordinary, the hind legs carrying 

 much light yellow pollen ; hind spurs white. Abdomen with 

 a sericeous surface ; in addition to the apical hair-bands 

 there are thin basal ones; hind coxse with a small apical 

 tooth or spine on inner side. 



Related to H. eumorpha (Ckll.) and H. rhodocerata (Ckll.), 

 but easily known by the thoracic sculpture and large amount 

 of black hair. 



Hab. Kenworthy, San Jacinto Mts., California, 5000 feet, 

 June 8 {F. Grinnell, Jr.). 



Diandrena piithua, sp. n. 



J . — Length about 61 mm. 



Green ; similar to D. nothc calaidis, Ckll., except that the 

 hair of the face is wholly white, without any black ; the eyes 

 are rather broader and very prominent ; the size is rather 

 less ; the spurs are white; and the area of metathorax has no 



