1892.] 238 



The six following genera contain small shining hlack species, with 

 closed and pedunculated first posterior wing cells, naked eyes, and 

 facialia, and short antennae, which are so much alike that it is difficult 

 to find any good diagnostic characters, and to place them in satisfactory 

 groups ; I shall, therefore, arrange them in another short analytical 

 table before describing them.* 



1 (10) Alulro small, or of moderate size. 



2 (8) Outer cross vein placed nearly in the centre between the inner cross vein 



and the bend of the fourth vein. 



3 (4) (5) Cheeks (not facialia) ciliated with a row of fine setse, continuous with 



the fronto-orbital bristles Clista, Mgn. 



4 (3) (5) Cheeks armed on their lower part with a row of strong bristles... 



Rhinophora, Mgn. 



5 (3) (4) Cheeks bare, or having only a few scattered fine hairs. 



6 (7) Chin large and setose FOBTISIA, End. 



7 (6) Chin small and smooth. 



8 (2) (9) Outer cross vein much nearer to the inner one than to the bend of the 



fourth vein Plesina, Mgn. 



9 (2) (8) Outer cross vein nearer to the bend of the fourth than to the inner 



cross vein Phyto, Dsv. 



10 (1) Alulse very large, and anal segments of female armed with claspers or 

 forceps Leucostoma, Mgn. 



38.— CLISTA, Mgn. 



Leucostoma, p. Zett. 



Qen. ch. — Eyes long and nude, extending over most of the side 

 of the head, approximate in the male ; chin small but setose ; epistome 

 prominent ; vibrissae large ; fronto-orbital bristles in a double row 

 behind in both sexes, and the inner row continuous with a line of fine 

 setae, which extends to the bottom of the narrow cheek ; facialia bare ; 

 antennae with the second joint nearly as long as the third ; arista sub- 

 pubescent ; abdomen without discal setae ; stalk of the first posterior 

 wing-cell about two-thirds of the length of the outer cross vein, 

 which is placed nearly midway between the bend of the fourth vein 

 and the inner cross one, or sometimes rather nearer to the former. 



1 (2) Abdomen with white fasciae 1. mcsrens, Mgn. 



2 (1) Abdomen immaculate 2. csnescens, Zett. 



C. M^EENS, Mgn. 

 Black and glabrous ; frontalia shining black behind, and with a central black 



* This table differs in some points from that placed at the beginning of my paper. 



