36 COQUILLETT [4 22 ] 



Island, Alaska, July S to 12 : Twenty-three specimens. The type lo- 

 cality of this species is the White Mountains, New Hampshire. 



Platypalpus flavirostris Loew. 



Platypalpus flavirostris LOEW, Berliner Ent. Zeitsch., p. 90, 1864. 



Popof Island, Alaska : Five specimens, collected July 8 to n. The 

 type locality of this species is also the White Mountains, New Hamp- 

 shire. Some of the specimens have the head yellow, as in P. tersus 

 Coq., from which they may readily be distinguished by the broad 

 front ; in both sexes the front at its narrowest part is about one-third 

 as wide as the distance from the lowest ocellus to the insertion of the 

 antennae, greatly widening upwardly, whereas, in tersus the front only 

 slightly widens upwardly, and at its narrowest point is only about one- 

 eighth as wide as the distance from the lowest ocellus to the antennae. 



Platypalpus diversipes sp. nov. 



Black, the palpi and halteres whitish, legs yellow, bases of coxae, 

 upper side of front femora, broad apices of other femora, of the tibiae 

 and whole of tarsi, except base of the first joint, black ; head polished, 

 the face opaque, whitish pruinose, third joint of antennae only slightly 

 longer than broad, body polished, pleura opaque, thinly gray pruinose ; 

 front femora considerably thickened, about two-thirds as thick as the 

 middle ones ; wings hyaline, veins yellowish brown, first and second 

 basal cells subequal in length. Length 1.5 mm. Three males and 

 twelve females, collected July 8 to 13. 



Habitat. Popof Island, Alaska. 



Type. Cat. no. 5233, U. S. National Museum. 



Platypalpus gilvipes sp. nov. 



Black, the first two joints of antennae, palpi, halteres and legs, in- 

 cluding the coxae, yellow, last joint of tarsi brown; third joint of an- 

 tennae about twice as long as wide, head polished, the face opaque, 

 white pruinose, body polished, the front end of pleura to posterior 

 side of front coxae, also the lateral margins of metanotum, encroach- 

 ing slightly on the pleura, opaque, gray pruinose ; front femora no- 

 ticeably thickened, about two-thirds as thick as the middle ones ; wings 

 hyaline, veins brown, first and second basal cells subequal in length. 

 Length 2 to nearly 3 mm. Four males and five females, collected 

 July S to 12. 



Habitat. Popof Island, Alaska. 



7ype. Cat. no. 5234, U. S. National Museum. 



Closely related to latcralis, but in that species the entire pleura, ex- 



