THE LOCUST-TREE BORERS. 411 



by the caterpillar, are weaker than the rest of the stem, 

 which therefore easily breaks off at these places. My at- 

 tempts to complete the history of this insect have not been 

 successful hitherto. 



The second kind of borer of the locust-tree is larger 

 than the foregoing, is a grub, and not a caterpillar, which 

 finally turns to the beetle named Cbjtus pictus, the paint- 

 ed Clytus, already described on a preceding page of this 

 work. 



The third of the wood-eaters to which the locust-tree is 

 exposed, though less common than the others, and not so 

 universally destructive to the tree as the painted Clytus, is a 

 very much larger borer, and is occasionally productive of great 

 injury, especially to full-grown and old trees, for which it 

 appears to have a preference. It is a true caterpillar (Fig. 

 203), belonging to the tribe of moths under consideration, 



Fig. 203. 



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 continuing them 

 through the bark to the outside of the trunk. Before trans- 



CD 



forming, they line these passages with a web of silk, and, 

 retiring to some distance from the orifice, they spin around 

 their bodies a closer web, or cocoon, within which they 

 assume the chrysalis form. The chrysalis (Fig. 204) meas- 



