Insect Study 



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may emerge in the spring. This caterpillar knows more botany than 

 some people do, for it makes no mistake in distinguishing a compound 

 leaf from a simple one. When it uses a leaflet of hickory for its cocoon, 

 it fastens the leaflet to the mid stem of the leaf and then fastens the stem 

 to the twig. The male pupa is much more slender than that of the female. 

 The moths do not issue until May or June. 



The moth works its way out through the valve at the top of the cocoon. 

 The female is a large, reddish brown moth with markings resembling 

 somewhat those of the cecropia. The male is very different in appear- 

 ance; its front wings have very graceful, prolonged tips, and both wings 

 are almost black, bordered with ash color. The promethea moths differ 

 somewhat in habit from the other silk-worms, in that they fly during the 

 late afternoon as well as at night. The eggs are whitish with brown stain, 

 and are laid in rows, a good many on the same leaf. 



The caterpillars, as they hatch from the eggs, have bodies ringed with 

 black and yellow. They are sociable little fellows and live together side 

 by side amicably, not exactly "toeing the mark" like a spelling class, but 

 all heads in a row at the edge of the leaf where each is eating as fast as 



possible. When t h ey 

 are small, the caterpil- 

 lars remain on the under 

 side of the leaves out of 

 sight. In about five 

 days, the first skin is 

 shed and the color of the 

 caterpillar remains about 

 the same. Four or five 

 days later, the second 

 molt occurs, and then 

 the caterpillar appears in 

 a beautiful bluish green 

 costume, with black 

 tubercles, except four 

 large ones on the second 

 and third segments, and 

 one large one on the 

 eleventh segment, which 

 are yellow. This cater- 

 pillar has an interesting 

 habit of weaving a carpet of silk on which to change its skin ; it seems 

 to be better able to hold on while pushing off the old skin, if it has the 

 silken rug to cling to. After the third molt, the color is a deeper greenish 

 blue and the black tubercles are smaller, and the five big ones are larger 

 and bright orange in color. After the fourth molt, which occurs after a 

 period of about five or six days, the caterpillar appears in its last stage. 

 It is now over two inches long, quite smooth and most prosperous looking. 

 Its color is a beautiful, light, greenish blue, and its head is yellow. It has 

 six rows of short, round, black tubercles. The four large tubercles at the 

 front end of the body are red, and the large tubercle on the rear end of the 

 body is yellow. 



The cynthia is a beautiful moth which has come to us from Asia; it is 

 very large with a ground color of olive-green, with lavender tints and 



' 



Promethea caterpillars. 



Photo by M. V. Slingerland. 



