Sept. 1898.] COQUILLETT : On DIPTEROUS FAMILY SCATOPHAGID^E. 161 



Osten Sacken catalogue it bears the name of Cordyluridse, but since the 

 genus Scatophaga is the oldest one in this family, it is desirable to name 

 the family after it. 



The European genera and species of this family have quite recently 

 been monographed by Mr. Theodore Becker,* and a translation of his 

 tables of subfamilies and genera, in an abbreviated form, is given by Dr. 

 Williston in his recent manual. Owing to the faulty definitions of the 

 subfamilies, whereby certain genera which possess a given character are 

 placed in a subfamily in which this character is expressly stated to be 

 absent, and the further difficulty of separating subfamilies by such 

 Walkerian phrases as "face short," "face long," it will be quite im- 

 possible for the student to refer his species to its proper genus by the use 

 of these tables, and I have therefore constructed an entirely new one 

 which contains all of the genera belonging to this family known to me 

 to occur in this country. 



TABLE OF GENERA. 



1. Front tibiae destitute of an erect black spine on the inner side of each near the 



apex 2 



Front tibiae each bearing such a spine, third antennal joint rounded at the apex, 

 palpi destitute of an unusually long bristle at apex of each, one sternopleural 

 macrochseta Acanthocnema Becker. 



2. Third antennal joint produced in the form of a tooth at the anterior apical angle. . 3 

 Third joint rounded at the apex 5 



3. With three sternopleural macrochsetae, palpi destitute of an unusually long bristle 



at apex of each Orthochaeta Becker. 



With two sternopleurals, palpi near apex of each bearing a bristle which is nearly 



one-half as long as the palpi Chastosa, gen. nov. 



With only one sternopleural, palpi destitute of a single long terminal bristle. . . .4 



4. Palpi spatulate, about twice as long as wide Spaziphora Rond. 



Palpi more than four times as long as wide Opsiomyia, gen. nov. 



5. Apex of palpi each bearing a single bristle which is nearly as long as the palpi, 



one sternopleural 6 



Apex of palpi destitute of such a bristle 7 



6. Head at least as high as long, face nearly perpendicular Cordylura Fall. 



Head flattened, noticeably longer than high, face very oblique, greatly retreating 



below Acicephala, gen. nov. 



7. With only one sternopleural 8 



With two sternopleurals, frontal bristles strong, two or more pairs on anterior third 



of the front Hexamitocera Becker. 



8. Frontal bristles strong, two or more pairs on anterior third of the front. 



Scatophaga Meig. 

 Frontal bristles very short, none on lowest third of the front. Hydrom v za Fallen. 



* Bed. Ent. Zeitsch., May, 1894, pages 77 to 196. 



