MARCH, 1864. 249 



hue. In the costal cilia, just above the tip, are two minute 

 silvery-white streaks, black-margined internally. Beneath 

 the tip the wing is slightly varied with pale grayish. Hind- 

 wings grayish-brown, cilia the same. 



Antennas grayish-brown. Head in front and labial palpi 

 silvery-white. 



The larva mines the leaf of Brachyelytrum aristatum early 

 in July. The mine at this period is a blotch, taking up 

 most of the leaf, but the beginning is a threadlike line. My 

 specimens were taken on the 9th of July, at which time the 

 most of the mines I found were tenantless, and two of the 

 larvae were young. On the 12th of July, one of the larvae 

 left its mine to prepare for pupation ; this it did by weaving 

 a slight web in which the larva attached its anal prolegs, 

 with the head downward. The larva that spun up on the 

 12th, appeared as an imago on the 25th of July, 



Easton, Pennsylvania, 



ADELA, Lat. 



Hind-wings oblong-ovate, with moderate cilia. The sub- 

 costal vein is simple, attenuated towards the base. The dis- 

 coidal cell is closed by a doubly angulated vein, which 

 throws from the upper angle a discal branch, furcate near the 

 extremity and anastomoses with a false nervule in the middle 

 of the disk. The median vein is 3-branched, the upper 

 branch being medio-discal and closes the lower portion of 

 the disk. Submedian and internal veins distinct. 



Fore-wings oblong. The subcostal vein gives origin to four 

 marginal branches, the first arising near the base of the wing 

 and forms a secondary cell. (In the species described below, 

 Riding sella, the third marginal branch is furcate.) Two 

 discal branches are delivered to the hinder margin from the 

 discal vein. The median vein is 3-branched. The submedian 

 furcate at its base. 



Head rough, with hairlike scales ; face beneath rather 

 smooth. Ocelli none. Eyes remote in both sexes. An- 



