726 AN INTRODUCTION TO ENTOMOLOGY 



winter. At the upper end of the cocoon there is a conical valve-like 

 arrangement which allows the adult to emerge without the necessity 

 of making a hole through the cocoon. This structure is characteristic 

 of the cocoons of the moths of this and the following genus. See 

 Figure 211, page 189. 



The angulif era -moth, Callosdmia angidifera. — This is a somewhat 

 rare insect which closely resembles the Promethea-moth. Specimens 

 of it are usually a little larger than those of C. promethea, and the trans- 

 verse line and discal spots are more angular. The most important 

 differences, however, are presented by the male, which quite closely 

 resembles the female of the Promethea-moth in color and markings, 

 and thus differs decidedly from the male of that species. The male 

 of this species is nocturnal, differing in this respect from C. promethea. 

 The larva feeds on the leaves of the tulip-tree and of Magnolia. 

 It make its cocoon within a leaf or it crawls down the trunk of the 

 tree and spins its cocoon in the grass or fastens it to some object on 

 the ground. The cocoon usually has no stem and when made in a 

 leaf falls to the ground in it when the leaf falls. 



The Cecropia-moth, Sdmia cecrdpia. — This is the largest of our 

 giant silk-worais, the wings of the adult expanding from 125 to 160 

 mm. The ground color of the wings is a grizzled dusky brown, es- 

 pecially on the central area. The wings are crossed beyond the 

 middle by a white band, which is broadly margined without with red, 

 and there is a red spot near the apex of the fore wing just outside of a 

 zigzag line. Each wing bears near its center a crescent-shaped white 

 spot bordered with red. The outer margin of the wings is clay-colored. 

 The larva is known to feed on at least fifty species of plants, including 

 apple, plimi, and the more common forest trees. When full grown it 

 measures from 75 mm. to 100 mm. in length and is dull bluish green 

 in color. The body is armed with six rows of tubercles, extending 

 nearly its entire length, and there is an additional short row on each 

 side of the ventral aspect of the first five segments following the head. 

 The tubercles on the second and third thoracic segments are larger 

 than the others, and are coral-red. The other dorsal tubercles are 

 yellow, excepting those of the first thoracic and last abdominal seg- 

 ments, which with the lateral tubercles are blue; all are armed with 

 black bristles. The pupa is represented by Figure 929 and the cocoon 

 by Figure 930. 



The Cecropia-moth occurs from 

 the Atlantic Coast to the Rocky Moun- 

 tains. In the North Atlantic States 

 there is another species which resembles 

 it in general appearance but is much 

 smaller, expanding from 75 to 100 mm. 

 and is much less common ; this is Sdmia 

 -Sarma cccropia, pupa. Columbia. In the Far West the place 

 of the Cecropia-moth is taken by two 

 very closely allied species. In these the ground -color of the wings is 

 usually reddish or dusk}- brown. Sdmia gloveri is found in the Rocky 



