592 State Board of Agriculture, &c. 



brown. When full grown it is about one incli long, of quite 

 variable color, being sometimes light gray and all shades 

 from tliat to nearly black, and the head is brown, mottled 

 with black or dark brown. On the first joint back of the 

 head there is a yellowish shield. There are six true legs in 

 front and four false legs behind. The under side of the body 

 is yellowish, or greenish. Tlie ends of the body are some- 

 what darker than the middle, and there is a pale greenish 

 band along the middle of the under aide. " The chrysalis 

 is liglit brownish, tinged on the wing sheaths with dark 

 green." {RiIctj.) I have been particular in describing the 

 canker worm in its various stages, because there are several 

 similar insects of very different habits, and in dealing with 

 this or them it is important that the farmer know just what 

 insect he. is fighting. 



When the worm has reached its full size, it either creeps 

 down tlie trunk of the tree or lets itself down by a silk 

 thread, and, as it reaches the ground, burrows into it two 

 or three inches, and forms a cocoon of bits of eai'th and silk 

 threads, and remains in tlie chrysalis during the sum- 

 mer and winter, coming from it the following spring as 

 a perfect moth, when the females crawl towards the first 

 trees they find that are of suitable species, and ascend them, 

 the pairing taking place during the ascent. They not only 

 come from the cocoons in the spring, but to some extent 

 in the fall, and in mild days even in mid-winter. Harris 

 says that he has seen them in Massacliusetts every month 

 from October to March, and that there are more females 

 than males among those that come out in tlie fall and 

 winter, while the reverse is true of those that come out in 



