82 MYCBXOPHILID.i: . 



19. The 4th longitudinal vein forks beyond 



end of basal cell ; the costa extends 

 very little beyond tip of 3rd vein ; 



ocelli three, the middle one very small. Phronia, Winn., (pt.), 

 The 4th longitudinal vein " forks [p. 110. 



before end of basal cell ; the middle 

 ocellus present or absent Exechia, Winn., p. 112. 



20. Auxiliary vein ends in 1st longitudinal; 



the branches of the 5th vein diverging. Delop.sis, Skuse, (pt.), 

 Auxiliary vein ends free ; the branches [p. 118. 



of the 5th vein parallel along their 



apical third or half, or only very [p. 113. 



slightly convergent or divergent .... Mycktophila, Mg., 



The fact that several genera fall into two or more parts each of 

 this table proves that a satisfactory classification is still a 

 desideratum. My own special study of the family is too limited 

 to Oriental, and a certain number of European, species to permit me 

 to suggest any wide departure from the classification of Johannsen, 

 who appears to be the latest authority on the group. Distinctions 

 like those employed at points 8, 12, 16, and 17 may perhaps be 

 improved upon when a further knowledge of the world's species is 

 attained, no classification being satisfactory that is founded on the 

 species of one zoological region only. For this reason the order 

 in which the genera are described herein (which is intended to show 

 their affinities as nearly as possible) varies from that in which 

 they appear in this table. The absence of the posterior cross- 

 vein, in conjunction with the unforked 3rd vein, will easily 

 distinguish members of this subfamily. 



Genus GNORISTE, %. (PI. I, fig. 15.) 

 Gnoriste, Meigen, Syst. Besch. i, p. 243 (1818). 



Genotype, O. apiccdis, Mg., the original species. 



Head small, rounded, almost hemispherical, placed low upon the 

 thorax ; proboscis prolonged, beak-hke ; eyes elongated, somewhat 

 bulging, slightly emarginate at the base of the antennae ; ocelli 

 three, placed in a flattened triangle upon the broad front, the 

 middle one smaller. Palpi situated near the tip of the proboscis, 

 four-jointed, the 1st joint very small, the 2nd largest, the 3rd 

 and 4th oval. Antennae 16-jointed, arcuate, projecting forward, 

 the joints of the scapus bare, the flagellar joints compressed, 

 cyHndrical, pubescent. Thorax ovate, highly arched ; scutellum 

 small, semicircular in outline : metanotum steep, somewhat 

 arched. Abdomen long and slender, compressed, 7-jointed, in 

 the male with an almost clavate extremity and small forceps. 

 Legs long and slender, all tibiae with lateral setae, and with spurs. 

 Wings large, oval, microscopically setulose. Costa produced 

 beyond tip of 3rd longitudinal vein but not quite reaching wing- 

 tip ; subcostal cross-vein present, before the origin of the 3rd vein. 

 Auxiliary vein ends near middle of wing; 1st longitudinal a little 



