244 DIPTERA OF NORTH AMERICA. [PART II. 



with ciliatus. Five species Lave to be recorded as synonyms of 

 others ; these are radians Macq., as a synonym of longicornis 

 Fab., sipho Macq. of jucund us Loew, gemmifer Walk, of sijjho 

 Say, amatus Walk, of patibulatus Say, and inficitus Walker, 

 likewise of patibulatus Say. 



Table for the determination of the Species. 



( Tegulse with black cilia. 2 



( Tegulse with pale cilia. 15 



9 ( Wings with a darker picture. 3 



( Wings without picture. 9 



f Wings black, hyaline only at the tip and the hind margin. 

 I 1 dimidiatus Lw. 



j Wings hyaline, with two black fasciae connected on the anterior niar- 



L g' n - 4 



i Feet of the % predominantly yellow. 5 



( Feet of the % predominantly black. 6 



f First joint of the middle tarsi of the % with a few ordinary bristles 



upon the anterior side. 2 sipho Say. ' 



First joint of the middle tarsi of the % closely ciliated with short 



erect bristles on the anterior side. 3 scaber Lw. 



i Face hairy. 4 patibulatus Say. 



\ Face without hairs. • 7 



_ ( Feet in both sexes entirely black. 5 melampus Lw. 



I Feet in both sexes not entirely black. 8 



f Middle tibiae and first joint of the middle tarsi of the % ciliated on 



the upper side. 6 pilosus Lw. 



\ Middle tibiae and first joint of the middle tarsi not ciliated on the 



upper side in the £ . 1 jucundus Lw. 



[ First longitudinal vein much prolonged beyond the middle of the 



wing. 8 ciliatus Lw. 



9 i ° 



j First longitudinal vein reaching at the utmost as far as the middle of 



the wing. 10 



t Arista extremely elongated, apparently apical. 9 comatus Lw. 



\ Arista not very elongated, distinctly dorsal. 11 



I Fore tibiae of the % , fore and middle tibia? of the 9 > yellow. 

 10 chrysoprasius Walk. 

 All tibiae of the % , in the 9 also the femora, yellow. 12 



(The first joint of the middle tarsi of the % beset with crooked bris- 

 tles. 13 

 The first joint of the middle tarsi of the % plain. 14 

 f Tip of the abdomen of the % with moderately long hairs, 

 j • 11 scobinator Lvj. 

 ' j Tip of the abdomen of the % with exceedingly long hairs. 



12 caudatulus Lw. 



