LEPIDOPTERA, 



355 



of a large proportion of our common fruit and forest trees; 

 but we have found it more frequently on wild 'cherry and 

 ash than on others. The cocoons can be easily collected 

 during the winter from these trees. This is the best way to 

 obtain fresh specimens of the moths, which will emerge from 

 the cocoons in the spring or early summer. The cocoon 

 (Fig. 435) is interesting in structure. It is greatly elongated 

 and is enclosed in a leaf, the 

 petiole of which is securely fast- 

 ened to the branch by a band 

 of silk extending from the co- 

 coon ; thus the leaf and enclosed 

 cocoon hang upon the tree 

 throughout the winter. At the 

 upper end of the cocoon there 

 is a conical valve like arrange- 

 ment which allows the adult to 

 emerge without the necessity 

 of making a hole through the 

 cocoon. This structure is char- 

 acteristic of the cocoons of the 

 moths of this and the following 



genus. 



The Angulifera Moth, Callo- 

 sarnia angulifera (C. an-gu-lif'e- 

 ra). — This is a somewhat rare in- 

 sect which so closely resembles 

 the Promethea Moth that by 

 many it is considered a variety 

 of it. Specimens of it are usu- 

 ally a little larger than those of 

 Q. promethea, and the transverse 

 line and discal spots are more 

 angular. The most important 

 differences, however, are pre- 

 sented by the male, which quite closely resembles the female 



Fig. 435, — Callosaviia promethea, cocoon. 



