DOLICHOPUS. 25 



male sex only. The systematic . arrangement which follows the 

 dichotomic table subdivides the genus in groups, founded upon 

 easily perceptible characters common to both sexes. I think it 

 will be useful to retain these groups, or, at least, the principal 

 among them. 



Table for determining the Species. 



, ( Prevailing color of the feet black. 2 



I Prevailing color of the feet yellowish. 9 



9 f Cilia of the inferior orbit black. 3 



\ Cilia of the inferior orbit whitish. 4 



o f Face ochre yellowish. 1 gratus Lw. 



\ Face silvery white. 2 laticornis Lw. 



t ( First joint of hind tarsi with numerous bristles. 3 setifer Lw. 



\ First joint of hind tarsi with but few bristles. 5 



, ( Hind tibiae black only at the tip. 6 



I Hind tibiae quite black. 7 



("The black at the tip of the hind tibiae rather extended and not very 



sharply limited. 4 albiciliatus Lw. 



' I The black at the tip of the hind tibiae but little extended and sharply 



limited. 5 xanthocnemus, n. sp. 



H ( A considerable extent of the tip of the femora yellow. 6 tetricus, n. sp. 



I The extreme tip of the femora only somewhat yellow. 8 



f Lamellae of the hypopygium pointed. 7 acuminatus Lw. 



\ Lamellae of the hypopygium rounded ovate. 8 ovatus Lw. 



f Cilia of the inferior orbit black. 10 



v. Cilia of the inferior orbit pale. 11 



-. ( Fore coxae blackish. 9 pachycnemus Lw. 



I Fore coxae yellow. 10 brevipennis Meig. 



, , f Tegulfe with pale cilia. 12 



\ Tegulae with black cilia. 23 



, f Antennae black, at the utmost, the first joint almost red. 13 



I Antennae altogether, or at least their larger portion, yellowish red. 21 



1 n ( Fore coxae dark beyond the middle. 11 longimanus Lw. 



I Fore coxae pale. 14 



1 . ( Tip of the hind tibiae decidedly blackish. 15 



C Tip of the hind tibiae not or very slightly infuscated. 16 



lf . f Fore tarsi only ferruginous-brownish; 12 brevimanus Lw. 



\ Fore tarsi blackened from the tip of the first joint. 13 socius Lw. 



, ,, f Hind tarsi entirely black. 17 



I Basis of the hind tarsi pale to a considerable extent. 19 



, - f Hind femora of the male not ciliated. 14 nudus, n. sp. 



\ Hind femora of the male ciliated. 18 



