108 THE PESTS OF THE FARM. 



aideration, is reddish, above, and white beneath, with the head and 

 top of the first ring brown and shelly, and there are a few short 

 hairs arising from minute warts thinly scattered over the surface of 

 the body. When fully grown, it measures two inches and a half, 

 or more, in length, and is nearly as thick as the end of the little 

 finger. These caterpillars bore the tree in various directions, but 

 for the most part obliquely upwards and downwards through the 

 solid wood, enlarging the holes as they increase in size, and con- 

 tinuing them through the bark to the outside of the trunk. Before 

 transforming, they line these passages with a web of silk, and, re- 

 tiring to some distance from the orifice, they spin around their 

 bodies a closer web, or cocoon, within which they assume the chry- 

 salis form. The chrysalis measures one inch and a half or two 

 inches in length, is of an amber color, changing to brown on the 

 forepart of the body ; and, on the upper side of each abdominal 

 ring, are two transverse rows of tooth-like projections. By the help 

 of these, the insect, when ready for its last transformation, works 

 its way to the mouth of its burrow, where it remains while the 

 chrysalis skin is rent, upon which it comes forth on the trunk of the 

 tree a winged moth. In this its perfected state, it is of a grav color ; 

 the fore-wings are thickly covered with dusky netted lines and 

 irregular spots, the hind-wings are more uniformly dusky, and the 

 shoulder-covers are edged with black on the inside. It expands 

 about three inches. The male, which is much smaller, and has 

 been mistaken for another species, is much darker than the female, 

 from which it differs also in having a large ochre-yellow spot on the 

 hind-wings, contiguous to their posterior margin. Professor Peck, 

 who first made public the history of this insect, named it Cossus 

 Hcbinice, the Cossus of the locust-tree. It is supposed by Professor 

 Peck ip remain three years in the caterpillar state. The moth 

 comes forth about the middle of July. 



Our fruit-trees seem to be peculiarly subject to the ravages of in- 

 sects, probably because the native trees of the forest, which origi- 

 nally yielded the insects an abundance of food, have been destroyed 

 to a great extent, and their places supplied only partially by orch- 

 ards, gardens, and nurseries. Numerous as are the kinds of cater- 

 pillars now found on cultivated trees, some are far more abundant 

 than others, and therefore more often fall under our observation, 

 and come to be better known. Such, for instance, are certain gre- 

 garious caterpillars that swarm on the apple, cherry, arid plum-trees 

 towards the end of summer, stripping whole branches of their 



