LASIA.— CEEATUKGTTS. 167 



and the anterior branch of the third vein reaching the costa at the very end of the 

 first vein. 



That the venation in the genus Lasia is not always the same is proved by L. Metti, 



0. Sacken (cf. Lieut. Wheeler's Eeport on the Expl. and Surveys &c. v. Zool. p. 804), 

 in which the second vein reaches the costa at the end of the first (compare the figure, 



1. c). The species is from Arizona, and not unlike L. scribce in its general appearance. 

 Lasia auricoma, Westw. (Trans. Ent. Soc. Lond. v. p. 93), from Brazil, to judge from 



the description, may resemble L. scribce ; but it is only half an inch long ; the tarsi are 

 said to be " lutei," the tegulae " chalybese." 



Fam. ASILID-E. 



Section I. DASYPOGONINA. 



LEPTOGASTER. 



Leptogaster, Meigen, in Illiger's Magaz. 1803 ; Klassif. 1804. 



l. Leptogaster 



i 



Nineteen species of Leptogaster from North America have been described. I have 

 three Mexican species before me, two from Ciudad in Durango, collected by Mr. Forrer, 

 and one from Northern Sonora, collected by Mr. Morrison ; I do not venture to describe 

 these, though some of the existing descriptions very nearly apply to them ; the identi- 

 fication in any case would not by any means be certain. One of the species from 

 Ciudad, for instance, nearly answers the description of L. pictiptes, Loew, from Illinois. 



Two species have been previously described from Mexico : — 



Leptogaster fervens, Wiedem. Aussereur. zweifl. Ins. ii. p. 646. 



truquii, Bellardi, Saggio &c. ii. p. 87, t. 2. f. 18. — Mexico, Yautepec. 



CERATURGUS". 



Ceraturgus, Wiedemann, Analecta ent. &c. p. 12 (1824). 



There is not a single representative of this genus in the collections before me ; the 

 Central- American species previously described are : — 



Ceraturgus dimidiatus, Macq. Dipt. Exot. Suppl. ii. p. 35 (Dasypogon); Walker, 

 List &c. vi. p. 428 (Dasypogon); Bellardi, Saggio &c. ii. p. 61. — Mexico. 



ruji/pennis, Macq. loc. cit. p. 32 (Dasypogon) ; Bellardi, Saggio &c. ii. 



p. 59. — Mexico. 



vitripennis, Bellardi, Saggio &c. ii. p. 60. — Mexico, Cuantla. 



geniculatus, Bigot, Ann. Soc. Ent. Fi\ 1878, p. 443. — Mexico. 



