286 



AN ECONOMIC ENTOMOLOGY. 



paler, while in the female we have, on the whole, an opposite 

 tendency. In the West, other species replace the americana, 

 but their habits remain essentially the same, and they may be all 

 treated in the same manner. During the winter the egg-masses 

 are easily seen after a little practice, and they can generally be 

 reached and cut down without trouble. Early in spring the 

 nests are prominent objects and easily destroyed, with the entire 

 colony. Where they are out of easy reach, simply spraying the 

 branches nearest to their nest will destroy them in a day or two. 

 In orchards in which spraying is systematically done for other 

 pests, these insects rarely get a foothold. 



The true silk- worm, Sericaria mori, though economically im- 

 portant, is hardly a proper subject for this work. Its history is 

 so well known, and has so many special books devoted to it, 

 that it is unnecessary to go into details here. 



In the family CossidcB we have a series of very peculiar moths, 

 really low in the scale of development, but formerly placed about 

 here in the classification and conveniently so treated. The cater- 

 pillars are all wood-borers, living from two to four years in the 

 trunks or roots of trees. They are white, or with a faint red or 

 yellow tinge, more or less black spotted, and with short, bristly 

 hairs. The head is large and horny, usually black, and the jaws 

 are stout and prominent. When full-grown they are from two 

 to three inches in length, and change to a rather slender, cylin- 

 drical pupa an inch to an inch and a half in length, depending 



upon the species and sex. 

 319- This pupa is furnished with a 



series of spines around the 

 edges of each segment and 

 sometimes also with a chisel- 

 Pupa of the goat-moth. l^^e protubcrauce on the head- 

 case. When ready to trans- 

 form, it works itself by a twisting and wriggling motion through 

 the bark and for half its length out into the open, holding fast 

 by the spines on the abdominal segments. The adults, known as 

 "goat-moths," from a rank odor peculiar to them, have rather 

 narrow, pointed wings and a long conical abdomen. The 

 females are heavy fliers, and both sexes are attracted to light, 

 though rarely seen otherwise. The head is small, very much 



