INSECTS 



times the tops of the eggs are entirely bare. The eggs 

 are placed in a single layer next the bark (Fig. 144 B), 

 and there are usually 300 or 400 of them. They look like 

 little, pale-gray porcelain jars packed closely together 

 and glued to the twig by their rounded and somewhat 

 compressed lower ends. The tops are flat or a little 

 convex. Each egg is the twenty-fourth of an inch in 

 height, about two-thirds of this in width, and has a 

 capacity of one caterpillar. The covering is usually half 

 again as deep as the height of the eggs, but varies in thick- 

 ness in different specimens. The outer surface is smooth 

 and polished, but the interior is full of irregular, many- 

 sided air spaces, separated from one another by thin 

 partitions (B). 



Wherever the covering of an egg mass has been broken 

 away, the bases ot the partition walls leave brown lines 

 that look like cords strapped and tied into an irregular 

 net over the eggs (B), as if for double security against 

 insurrection on the part of the inmates. But neither 

 shells nor fastenings will offer effective resistance to the 

 little caterpillars when they are taken with the urge for 

 freedom. Each is provided with efficient cutting in- 

 struments in the form of sharp-toothed jaws that will 

 enable it to open a round hole through the roof of its cell 

 (Fig. 1 44 C). The superstructure is then easily pene- 

 trated, and the emerging caterpillar finds itself on the 

 surlace of its former prison, along with several hundred 

 brothers and sisters when all are out. 



All this time the members of that unfortunate brood 

 we noted first have been clinging benumbed and motion- 

 less to the silk network on the covering of their deserted 

 eggs. The cold continues, the clouds are threatening, 

 and during the afternoon the hapless creatures are 

 drenched by hard and chilling rains. Through the night 

 following they are tossed in a northwest gale, while the 

 temperature drops below freezing. The next day the 

 wind continues, and frost comes again at night. For three 



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