52 C. H. TYLER TOWNSEND. 



yellow pilose. Autennse wholly yellow, with an orange tinge, the arista darker 

 terminally. Upper part of front darker, black pilose, vertex yellow pilose. Tho- 

 rax yellowish pilose, with three broad blackish vittse, reaching scutellum, leaving 

 four yellowish vittfe. Scutellum yellowish ; pile of thorax and scutellum yellow, 

 of pleurse thickly yellow; that of abdomen short and chiefly yellow. First ab- 

 dominal segment gray pollinose, except on posterior angles ; yellow spots of second 

 segment very distinctly interrupted ; of third almost joined by two yellow trian- 

 gular elongate spots; fourth with yellowish pollinose separated spots shaped like 

 those of second, fifth yellow pollinose. Black of second segment expanded 

 broadly on each side anteriorly, running on to sides of first segment. Second 

 segment with a very narrow yellow hind margin; third with a broader yellow 

 margin, somewhat pollinose anteriorly in middle ; fourth with a yellow margin 

 of same width and a grayish pollinose band next in front of it. Legs yellow ; 

 middle and front femora at base, hind femora in middle, hind tibiae at tip. and 

 hind tarsi except tip, blackish ; hind tibije near base, and hind knees, brownish > 

 also front tibiae narrowly on inside at tip. Wings fu.scous-hyaline, dilute flavous 

 on more than basal half. 



Constantine, Mich., August 26. One male ; agrees well with 

 Bigot's description, but as the latter is not detailed the identity can- 

 not be certain. 



ii:2. Helopliilus latifrons Loew. 



Las Cruces, N. Mex. One female, June 8. Length 12 mm. 

 Agrees well with Williston's description ; antennae black, arista 

 3'ellow. 



G3. Helophilus siniilis Mcq. 



Constantine, ]\Iich. One male and one female, August 28 and 8L 

 Length 12-13 mm. Agree well with the distinctive characters 

 pointed out by Williston wherein the species differs from luiifrotis. 



l>4. Mallota cimbiciforniis Fall. 



Washington, D. C. (Marlatt), May 17. One male. Length only 

 10.5 mm. Belonging to the form cimbiciformis, unspurred ; pile of 

 fi-ontal triangle and face yellowish white, sparse ; brown spot of 

 wings faint ; pile of front and middle legs more or less yellowish ; 

 pile of abdomen all black, except at base. 



65. Tropidia incaua n. sp. 



Length about 7 mm. Differs from female of T. qiindrafa as follows: Face and 

 cheeks entirely shining black, somewhat silvery pollinose. Face distinctly con- 

 cave in profile. Antenuai dark reddish or reddish brown. No median pollinose 

 stripes apparent on thoracic dorsum ; whole thoracic dorsum and scutellum shin- 

 ing black, the latter without any yellow on the border ; pleurse also shining black. 

 Abdomen pale red, first segment black, except hind angles ; second segment with 

 a median black vitta, which is expanded anteriorly, coalescing with the black of 

 first segment ; posteriorly it is also widened about half way to lateral edge on 



