COCOONS OF SOME OF THE SPECIES OF THE GENUS ACROBASIS 53 



under side the fore wings are yellow gray with a smoky lint outwardly, 

 the posterior margm and line in the cilia distinctly outlined ; at the base, 

 just beneath the costal margin, is a heavy, short, tapering black patch ; 

 the discal dots are not distinctly separated. The hind wings are a smoky 

 yellow gray, darkest outwardly, with the posterior margin and a line in 

 the cilia distinct ; on the under side the wings are paler but similarly 

 marked. Expanse, 18 mm. 



One male, July, 1910, and two females, July, 1912, from East River, 

 Connecticut (Chas. R. Ely). 



Type, No. 15740, U. S. Nat. Mus. 



The females of this species are much darker than the male, the whitish 

 tints tending toward yellowish and the rosy tints toward a violet gray. 

 The black markings on the legs and at base of the fore wing, on the 

 under side, of the male are absent in the females. 



This insect most nearly resembles A. feltella Dyar, from which it 

 may be separated by its leurger size and by the fact that A. feltella Dyar 

 has, on the under side of the fore wing of the male, a heavy dark shad- 

 ing along the upper margin of the cell while the costal margin is con- 

 trastingly whitish. 



Acrobasis kearfottella Dyar. 



This species, which feeds on hickory, has the habit of attaching its 

 cocoon to a leaf, selecting usually a point near the base of a leaflet, on 

 the under side. The larvae are probably gregarious at times, as the 

 cocoons may be found in groups of three or four, arranged parallel to one 

 another, with their bases toward the leaf stalk. The leaflet is drawn 

 somewhat loosely about the group of cocoons and the tip is usually eaten 

 away. The individual cocoons comprising the clusters are about 20 mm. 

 long by 4 mm. in diameter at the widest point, horn shaped, nearly 

 straight, in some cases, but often more or less bent or twisted. The outer 

 surface is covered with a dirty white silk, except at the extremity where 

 the rough black frass remains uncovered. Adults were obtained from 

 cocoons and taken at light from July 2 to July 1 0. 



Acrobasis coryliella Dyar. 



This species was named by Dr. Dyar from a specimen bred on hazel. 

 On June 27, 1912, a number of Acrobasis cocoons were found by the 

 writer on hazel {Cor})lus americana). These cocoons differed in appear- 

 ance and were divided into two groups and put into separate breeding 



