Pomona College, Claremont, California 89 



with a broad spatulate blade, as in the mei/jrnii group of this genus, the apex deeply 

 notched medially. 



Habitat. — O regon . 



Holotype, $, Forest Grove, March 26, 1919, (F. R. Cole). 



Allotopotype, 9. 



Paratopotypes, 2 5 s; paratypes, 1 <5 , 1$, Hillsboro, April 1, 1919, (F. R. Cole). 



This little species is evidently the Western representative of the common 0. 

 meigenii (O. S.) of the Eastern States, its general appearance being very like that 

 species. In the structure of the male hypopygium, however, it runs closes to O. 

 cornuia (Doane), which may be told by the different color of the wings and the 

 structure of the hypopygium. 



Genus Gonomyia Meigen. 

 Gonomyia (Gonomyia) coloradica, sp. n. 



Belong to the blanJa group, closest to mallwsoni Alex.; general coloration yel- 

 lowish, the praescutum with three broad, confluent stripes of reddish brown; wings 

 with the petiole of cell M2 long; male hypopygium with the structural details very 

 diflFerent from those in G. mathesoni. 



Male. — Length, about 4.5 mm.; wing about 6 mm. 



Rostrum, palpi and antenna; dark brown. Head dark. 



Pronotal scutum and the collate dark brown; pronotal scutellum pale. Mesonotal 

 praescutum with three broad, reddish-brown confluent stripes, the humeral regions 

 cephalad of the lateral stripes pale; scutellum pale. Pleura pale, indistinctly striped 

 with bro%vn. Halteres pale, the knobs dark brown. Legs with the coxje and trochanters 

 pale; femora light brown; remainder of the legs broken. Wings subhyaline, un- 

 spotted; stigma lacking; veins brown. Venation: almost as in G. mathesoni with the 

 following details different: R2 very oblique and apparently contiguous with the tip of 

 Rl ; R2-\-J not angulated before the middle of its length and without a faint spur of r 

 at this point; petiole of cell M2 much longer, one-half longer than the fused portion 

 of Cul and M. 



Abdomen light brown. Male hypopygium generally similar to that of G. mathe- 

 soni, differing as follows: The bifid pleural appendage is very similar in the two 

 species, in the present species with the needle-like tip of the longest arm abruptly pale. 

 The long, sinuous appendage in mathesoni is here represented by two, the longer of 

 which is pale throughout, flattened, the long tip acicular and almost straight; the 

 shorter appendage is flattened, before the tip a little expanded, with a long, slender, 

 curved black-tipped apex. Near the base of these pleural appendages is a flattened 

 subtriangular lobe which is covered with an abundance of short setae; in G. mathesoni, 

 this appendage is very small, cylindrical, with but few setae and with a distinct finger- 

 like spinous lobe on one side. Penis-guard distinctly trifid at its apex, the lateral black 

 spines directed almost caudad, setigerous at their bases; a shorter median pale lobe. 



Habitat. — Colorado. 



Holotype, <J , Longview, June 24, 1916 (E. C. Jackson). 



Type in the collection of the United States Biological Survey. 



