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Home Nature-Stl'dv Course. 



on the under side of the leaf. They hatch from ten to fifteen days after 

 being laid. 



The caterpillar. — When first hatched the caterpillar has a large, red- 

 dish head and the body is yellow. Later the body turns green, the back 

 being bluish in tint ; the tubercles are yellow. It changes its skin at inter- 

 vals, as do the other silk-worms, but tlie color of the body does not 

 change noticeably. When the caterpillar has reached its full growth, its 

 body is green with oblique yellow stripes on each of the abdominal seg- 

 ments. The tubercles are orange, sometimes red. The shield on the rear 

 end of the body is edged with brown and the head is reddish-brown. 

 The segments of the body are deep and sharp at the edge. The cater- 

 pillar has a way when resting, of drawing itself up so that its segments 



Polyphemus caterpillar fully grown. 



look like a half shut accordion. It will erect the front part of the body 

 if disturbed and hold itself thus motionless for a long time and un- 

 doubtedly thus escapes notice, as it resembles a serrate edged leaf. 



TJie cocoon. — This is quite different in shape from that of the 

 cecropia or ])romethea. It is a broad, blunt oval and is spun within at 

 least two leaves and often with other leaves in the vicinity attached. 

 Usually when the leaves fall the cocoons go with them and lie safely 

 luider ine snow all winter. However, during recent years we have found 

 many polyphemus cocoons fastened to twigs and remaining on the tree 

 all winter. Whether this is a chance happening or the beginning of a 

 new habit, wc are unable to say. The cocoon is very solid, and is not 

 double walled, like that of the cecropia. 



