COCOONS OF SOME OF THE SPECIES OF THE GENUS ACROBASIS 55 



Hind wings smoky yellow gray, darkest toward the margins, the posterior 

 margins distinctly outlined with dark scales, followed by a similar line in 

 the cilia which are concolorous with the wings ; the lower side yellow gray 

 and posterior margins faintly outlined. Under this species are placed the 

 two males and a female, from cocoons on Ostr^a virginica referred to 

 above. Expanse, I 7 mm. 



Type, No. 15741, U. S. Nat. Mus. 



The cocoons of this insect are short, about I 4 mm. in length by 5 mm. 

 in width, covered with dirty white silk, darker toward the base, the apex 

 rounded with a closed opening similar to that of A . cor^liella Dyar. A 

 single male in the writer's collection, obtained July 10, 1911, from a 

 cocoon, on Carpinus americana, similar to those on Ostrya virginica, is 

 at present somewhat doubtfully referred to this species. 



The second lot of cocoons found on hazel, which were separated from 

 those producing A. coryliella Dyar, yielded, July 10 to 16, 1912, a 

 series of five adults, three males and two females. Four of these seem 

 to differ from any known species of Acrobasis, which is also true of a 

 male in the collection of the Connecticut Agricultural Experiment Station, 

 bred from a pupa collected on hazel, June 9, 1 9 1 1 , at Hartford, Con- 

 necticut, by Dr. W. E. Britton. The fifth specimen corresponds quite 

 closely to A. ostryella, but it is thought that the presence of this single 

 cocoon on hazel may have been accidentcJ. It is possible that A. ostry- 

 ella may feed on both Ostrya and Corylus, but this does not seem 

 probable and the writer believes there is sufficient ground for taking the 

 series of five specimens, which closely correspond to one another, as the 

 material for the description of the following new species, which is based 

 on one of them. 



Acrobasis secundella, new species. 



Head and antennae yellow gray ; labial palpi fuscous ; maxillary palpi 

 yellow gray ; thorax yellow gray above with a slight rosy tint, white be- 

 low ; abdomen yellow gray, annulate with brown on each segment. The 

 legs are whitish speckled and shaded with brown, almost pure white on 

 inner side near thorax ; the tibiae of the hind legs with a brush of ap- 

 pressed long yellowish scales above. The fore wings are a dark brown 

 gray, the basal area, to just beyond the scale ridge, paler in color with 

 whitish and pinkish scales ; the scale ridge thick and black edged with 

 white toward base and followed by a faint pinkish shading ; the medicui 



