242 long's second expedition. 



I described that insect in tlie year 1819, before any account of 

 that new genus had reached this country, otherwise I certainly 

 should have adopted it. 



LASIOPTERA Meigen. 



L. VENTRALis. — Body blackish-brown; antennae 18-jointed, 

 hairy, joints subglobular, rather transverse, and placed close to 

 each other, basal joint whitish; thorax and terguni immaculate ; 

 feet whitish, exterior side of the tibiae blackish ; tarsi blackish, 

 first joint very short; venter whitish in the middle; wings with 

 a narrow, blackish, costal margin, which is gradually narrowed 

 to the tip. 



9 Length rather more than one-twentieth of an inch. 



I caught this species in the garden of the University of Penn- 

 sylvania. 



CECIDOMYIA Latr. 



C. ORNATA. — Carneous ; wings spotted. 



Inhabits Pennsylvania. 



Body varies in color from a very pale flesh color to a deep red ; 

 antennas and feet whitish ; wings with five or six dusky spots oc- 

 casioned by the greater density of the hair of the surface in those 

 parts. 



Length to the tip of the wings nearly one-tenth of an inch. 



This is most probably the prettiest species of the genus ; [358] 

 it occurred on a window in Philadelphia on the 13th of Septem- 

 ber. 



PSYCHODA Latr. 



P. ALTERNATA. — Wings acute at tip, with a small black spot 

 at the tips of the nervures. 



Inhabits Pennsylvania. 



Body pale yellowish-white ; abdomen dusky ; wings ovate- 

 lanceolate, acute at tip, cinereous with an obsolete pale band on 

 the middle and base ; the alternate nervures of the posterior 

 margin at their tips and the tips of the nervures of the anterior 

 margin with a black spot; spots of the posterior margin more 

 distinct. 



Length to the tip of the wings more than one-tenth of an inch. 



