168 DIPTEEA. 



MICKOSTYLUM. 



Microstylum, Macquart, Dipt. Exot. i. 2, p. 26 (1838). 



The only described Central- American species is : — 



Microstylum fulvigaster, Bigot, Ann. Soc. Ent. Fr. 1878, p. 410. — Mexico. 



OSPRIOCERUS. 



Ospriocerus, Loew, Centur. vii. no. 51 (1866). 



1. Ospriocerus ? 



Hah. Mexico, Northern Sonora (Morrison). 



Two specimens from the above-named locality differ from all the described species in 

 having the abdomen, including the venter, red, with only the first segment and the 

 anterior corners of the second black, and the eighth segment darker. The colouring 

 in this genus being variable, it is possible that these specimens are varieties of described 

 species. The other characters denning the species have not been sufficiently insisted 

 on in the descriptions, and under such circumstances I cannot determine whether the 

 species before me is new or not. 



2. Ospriocerus seacus. 



Dasypogon ceacus, Wiedem. Aussereur. zweifl. Ins. i. p. 390. 

 Ospriocerus ceacus, 0. Sacken, Western Dipt. p. 290 \ 



Asilus (Dasypogon) abdominalis, Say, Long's Second Exped. p. 375 2 ; Compl. Wr. i. p. 255. 

 (?) Dasypogon spathulatus, Bellardi, Saggio &c. ii. p. 82, t. 1. f. 9 8 (synonymy apud Loew, Centur. 

 vii. no. 51). 



Hdb. Western United States x 2 . — Mexico 3 . 



ABLAUTATUS. 



Ablautus, Loew, Centur. vii. no. 63 (1866). 

 Ablautatus, Loew, Berl. ent. Zeit. 1874, p. 377. 



1. Ablautatus trifarius? 



Ablautatus trifarius, Loew, Centur. vii. no. 63. 



I have a single specimen from Northern Sonora, which I doubtfully refer to this 

 species. 



STENOPOGON. 



Stenopogon, Loew, Linn. Entom. ii. p. 453 (1847). 

 This genus, as well as Scleropogon, is abundantly represented in New Mexico and 



