THE CANADIAN ENTOMOLOGIST. 



Sides of face with black bristles ; pleurae not with yellow hair 4 



4. — Abdomen reddish yellow, with or without small black spots ; claws 



and pulvilli of male small sequax, n. sp. 



Abdomen largely black ; claws and pulvilli of male large . . exul, n. sp. 



GoNiA FRONTOSA Say, J. Acad. Phil, vi., 175; Compl. Wr. ii., 365.' 

 Gonia philadelphica Macquart, Dipt. Exot. ii., 3, 51, 6. 

 .? Gonia albifrons Walker, List, etc., iv., 798. 

 % . Length 9.5-10 m.m. Face and front light yellow, with a silvery, 

 or slightly golden sheen ; front a little translucent on the sides when seen 

 from above ; face on the sides with short black bristles, and a number of 

 longer ones near the sides of the median depression ; median depression 

 in its greatest width about as wide as the least width of the sides of the 

 face; cheeks with short black bristly hairs only. Antennae blackish 

 brown, the second joint and base of third yellowish ; second joint about 

 one-third the length of the third ; second joint of the arista not more than 

 three-fifths the length of the third. Palpi yellow. Dorsum of thorax 

 black ; the humeri, post-alar callosities, and scutellum in large part, luteous 

 yellowish ; dorsum, when seen from behind, distinctly gray pollinose, 

 leaving four slender stripes. Bristles of scutellum long, reaching to base 

 of third abdominal segment. Abdomen deep shining black ; the second 

 segment with a very narrow, the third with a narrow, the fourth with a 

 moderately broad, basal white-pollinose cross band. Wings nearly hyaline 

 behind ; the costal, subcostal and first basal cells very distinctly tinged 

 with brown. 



^. Length 9-10 m.m. Front distinctly narrower, and more project- 

 ing below. Median facial depression deeper, larger, and longer, broader 

 below than the sides of the face. Antennae larger and longer, the second 

 joint shorter, not more than one-fifth or one-sixth as long as the third ; 

 arista shorter than the joint, its second joint curved, three-fifths, or three- 

 fourths as long as the third. Dorsum of the thorax a little more hairy. 

 Abdomen more elongate or egg-shaped, the sides of the second and third 

 segments sometimes reddish. Tarsal joints of front feet a little less disci- 

 form, the claws a little longer. 



This description is drawn from twelve females, mostly collected to- 

 gether in Fairmount Park, Philadelphia, by Mr. E. Keen, and eight males 

 from Minnesota, collected together. They are all closely related, and 

 their absolute identity seems certain. Among these specimens, however, 



