DIPTEEA. 



325 



13. Erax splendens, sp. n. (Tab. VI. fig. 5, <? .) 



6 . Face yellow on the sides ; gibbosity covered with long, bushy, light yellow hair, scarcely different in 

 colour from the beard. Palpi with yellow hair. Upper part of the occiput and front, and the first two 

 joints of the antenna, with black hair and bristles. Thorax deep brownish-black, the mesonotal stripes 

 feebly differentiated ; hair on the posterior part of the mesonotum and on the scutellum black. Abdomen 

 deep black ; first three segments with black hair ; fourth, fifth, and sixth segments silvery-white, the 

 lateral margins brown, the white hair directed outwards ; hypopygium of moderate size, with bushy 

 black hair below. Legs black, the femora greenish; the femora and tibiae with long hair on the 

 underside, that of the four posterior femora black, that of the front femora longer and for the most part 

 yellow ; hair of the tibia? in part black ; four anterior tarsi with long yellow hair on the posterior side ; 

 hair of the front coxse bushy and yellow. Wings tinged with brownish ; furcation of third vein a little 

 distance beyond the anterior cross-vein, the branch with a long stump ; costa not appreciably expanded. 

 Length 25 millim. 



Hab. Mexico, San Bias in Jalisco {Schumann). 



One specimen. The front and hind tibiae and metatarsi have short, abundant, 

 golden-yellow pile on the inner side. 



14. Erax quadrimaculatus. 



Erax quadrimaculatus, Bellardi, Saggio etc. ii. p. 44, t. 2. f. 13 \ 



Hab. Mexico, Atoyac in Vera Cruz (H H. Smith), Playa Vicente \ Cordova. 



Two males and four females from Atoyac. This species will be recognized by its 

 large size, and by the sixth and seventh abdominal segments of the male having a 

 large triangular black spot in the silvery-white portions. The hind femora and tibiae 

 in the same sex have rather long light yellow hair. The female has a large silvery- 

 white spot on each side of the fifth segment. (See the next species.) E. quadri- 

 maculatus and E. bimaculatus were not identified by Osten Sacken. 



15. Erax bimaculatus. 



Erax bimaculatus, Bellardi, Saggio etc. ii. p. 45, t. 2. f. 11 l . 



Hab. Mexico \ San Bias and Santiago Iscuintla in Jalisco {Schumann). 



Two males and four females. This species is so closely allied to the preceding that 

 Osten Sacken, after comparing the types, suspected that they were identical. This, 

 however, is not the case. The males may be readily separated by the sixth and 

 seventh abdominal segments having only a little black streak, or being wholly 

 unicolorous ; the hind femora and tibiae, too, have much shorter hair on the 

 underside. The females are much more difficult to distinguish, but they may be 

 separated by the colour of the hair, which in both sexes is of a decidedly yellowish 

 tinge, while in E. quadrimaculatus it is almost pure white. That Bellardi described 

 the beard in E. quadrimaculatus as " pallide flava" and in E. bimaculatus as "flava" 

 makes it very probable that he did not have the female of E. quadrimaculatus before 

 him when he wrote the description of E. bimaculatus. 



