327 



eyes. Antennae simple in both sexes (except in A. insulsaria and A. subalbata, 

 where they are well pectinated on the basal half). Palpi short, slender, por- 

 rect; third joint short, not extending usually beyond the front. Fore wings tyith 

 the costa slightly arched, sometimes very straight ; apex sometimes slightly 

 subfalcate, outer edge usually bent .slightly on the first median venule. Hind 

 wings squarish, bent, or rounded. Venation : usually a small, diamond-shaped 

 subcostal cell (in insulsaria there is no cell) ; the first subcostal venule is some- 

 times very long, but differs much in length in the different species; in insul- 

 saria, it is no longer than the second subcostal venule. Hind legs with the 

 tibia 1 large and much swollen ; in the male with no spurs, or slender and 

 spurred, with all grades between; tarsi either one-fourth as long as the tibia? 

 or as long. Coloration : head often black in front ; body and wings white, 

 whitish-ochreous, or brown and red, with from two to four lines on the fore 

 wings. 



Larva. — "Caterpillars moderately long, but still slender, a little cari- 

 nated on the sides, stiff, with minute transverse folds, slightly swollen on the 

 posterior rings; head a little smaller than the prothoracic ring and retractile; 

 living principally on low plants and hiding by day. Chrysalides subterranean." 

 — Guene'e. 



This is a remarkably homogeneous group, and the species are nearly 

 always recognizable from the slightly-angulatcd wings, the short small head, 

 usually black in front, and the slender, short, feeble palpi, and by the invari- 

 ably simple male antennae. 



' The genus may be divided into three well-marked sections, as indicated 

 in the synopsis of the species. In A. ossulata, the venation differs from the 

 other species by the presence of two subcostal cells, while the origin of the 

 first and second median venules is very far apart. 



The most aberrant group is that represented by A. insulsaria, in which 

 the costa of the fore wings is remarkably straight, and there is no discal cell 

 (plate 4, fig. 3a); while the first subcostal venule is very short, and its origin 

 is situated beyond that of the fifth subcostal. These characters are certainly 

 of subgeneric value; but in other characters, the three species in this section 

 agree with the more normal forms. In the third and highest section (C), 

 there is much variation in the venation and proportions of the joints of the 

 leg, as well as in the degree of angulation of the wings; but there is a com- 

 mon fades to the section. In no large genus will there probably be found a 



