56 INSECUTOR INSClTlit MENSTRUUS 



portion of the wing, including the discal dots, light gray ; outer transverse 

 line very faintly indicated in the pale gray cilia ; discal dots separate and 

 distinct ; a slight depression in the costa nearly one-third from base ; on 

 the under side the wings are of a dark, shining yellow gray, with no 

 markings, and with concolorous cilia. The hind wings are yellow gray 

 with the posterior extremity edged with dark scales and a dark line in 

 the cilia parallel to the margin of the wing; on the under side the color 

 is a pale, shining yellow gray with somewhat paler cilia. 



Expanse, 1 6 mm. 



Type, No. 15742, U. S. Nat. Mus. ; East River, Connecticut, July 

 13, 1912 (C. R. Ely). 



The cocoons of this species are rough, nearly black, and taper consid- 

 erably toward the base, ending in a crooked horn-shaped prolongation 

 giving a total length of about 20 mm. and a maximum diameter of about 

 5 mm. 



Acrobasis rubrifasciella Packard. 



Hulst says in his original description of A crobasis comptoniella (Trans. 

 Am. Ent. Soc, XVII, 125, 1890) that he can "find no point of dis- 

 tinction in the imagines " between the latter species and A . rubrifasciella 

 Pack. A series of 15 or more specimens, obtained from cocoons on 

 alder, serves to show that the two species are easily distinguishable. In 

 A. comptoniella Hulst the red transverse band, which follows the scale 

 ridge, is in striking contrast to the rest of the wing, which, beyond this 

 point, is without the slightest red tint. In A . rubrifasciella Pack, the red 

 is paler, with more of a lilac tint, and the reddish shadmg does not take 

 the form of a sharply defined band, following the scale ridge, but tends 

 to be diffused more or less uniformly over the whole wing surface. 

 Rarely specimens are found in which the red is almost entirely absent 

 and in these cases the appearance approaches that of A . betulella Hulst. 



The cocoon is formed as the prolongation of the twisted or bent horn- 

 shaped case, which is 20 to 25 mm. long by 5 or 6 mm. in diameter 

 and is neatly rounded and closed at the outer end. 



Acrobasis comptoniella Hulst. 



This insect is said to feed upon both sweet fern {Compionia aspleni- 

 folia) and bayberry {Myrica cerifera). Cocoons were found in abun- 

 dance on both of these food plants, of the well known nearly globular 

 type, the cocoon being formed as a prolongation of the tapering and 



