Woodworkers 



it changes into a chrysalis, after the manner of the 

 clearwing-moths ; others aver that the change takes place 

 in the heart of the tree and that the perfect insects eat 

 their way out. That they are capable of doing so there 

 can be no doubt, for they can eat through lead-sheeting. 



In America, where, by the way, these insects are called 

 horn-tails, one species displays considerable ingenuity. 

 The female deposits her eggs in willow branches, and, 

 after doing so, she girdles the tree that is, removes a ring 

 of bark and in this manner prevents the further growth 

 of the wood which might conceivably crush her progeny. 



In a well-ordered scheme of nature it is fitting to ask : 

 Of what use are these destructive insects? Well, when 

 they first came upon the earth there were no such things 

 as houses and furniture, and in those days the insect 

 carpenters did good. Concerning them an eminent 

 entomologist said : " Probably no portion of the world 

 contains a larger number than the densely timbered 

 Amazon basin. In these great forests the Longicornia 

 [long-horned beetles] play a very important part in the 

 economy of nature. As soon as a tree dies and begins to 

 decay, their larvae, which are often of great size, attack 

 it and bore it through and through ; the work of boring 

 from their larger galleries is then taken up by various 

 smaller species of wood-boring beetles and free access is 

 then given to the rain and moisture which soon reduce the 

 trunks to a pulp and cause them not only to disappear, but 

 to act as manure to those trees that take their place." 



The second class of wood artificers with which we are 

 concerned are the gall-makers. Like the wood-borers, they 

 are of many species, and their galls are as varied as their 

 kinds. The resin-moth is a peculiar gall-maker which 

 takes advantage of the fact that cone-bearing trees, when 

 injured, give off resins freely. The female lays her eggs 

 at the tip of some fir-tree, and when the caterpillars hatch 

 they bite into the wood, thus causing the resin to flow. The 

 ingenious little insects put the sticky substance to good 



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