PESTS OF THE HOP CROP. 



135 



vines. The caterpillars when full-grown are very vora- 

 cious and will devour an entire leaf in an incredibly 

 short time. They are not frequently seen upon the 

 plant, since they drop readily when disturbed and 

 remain quiet for a few minutes, but they are quick 

 travellers when in motion. The eggs are laid on the 

 lower sides of the leaves, in batches of from 50 to 100 

 or more. The full-grown larva is an inch and a half 

 in length and very variable in color. It is covered 

 with stiff hairs, which are sometimes white, intermixed 

 with a few yellow or brown ones, or they are yellow, 

 red, brown, or almost black, sometimes darkest at both 



FIG. 68. WOOLLY BEAR CATERPILLAR, 

 a, Larva; >, pupa; c, adult. Natural size. (After Riley.) 



ends, or all colors mixed. The cocoon is mostly com- 

 posed of hairs of the caterpillar, and is spun in any suit- 

 able sheltered position. There is apparently but one 

 annual generation, and the insect hibernates both in 

 the caterpillar stage and in the pupal stage in its 

 cocoon. The figure which we give represents perhaps 

 the commonest variety of the caterpillar. 



THE SADDLE-BACK CATERPILLAR 



(Empretia stimulea, Clem.) 



This insect is another of the general feeders, and 

 will probably not play an important part as a hop 



