210 SAW-FLIES. CHAP. xi. 



was being cut up for firewood. They are called Saw-flies 

 " from the fact that the female possesses, posteriorly, 

 an instrument by which she perforates, or rather saws, 

 holes in trees, into which she drops her eggs. From 

 this it will be seen that the larvas are woodfeeders. 

 In this country they are by no means numerous, and 

 it is well that they are not, or our forests would shortly 

 disappear ; for, in places where they abound, such as 

 in Norway, they destroy hundreds of thousands of 

 trees in a season. It is only the growing and not the 

 dead wood that they attack. The young grubs, as 

 soon as they emerge from the egg, cut their way right 

 into the very heart of the solid timber, and there 

 they gnaw and bore in every possible direction. 

 By this means, the tree is either killed, or so injured, 

 that ultimately it pines and dies. The fly itself has 

 no English name^ but is known to entomologists by 

 the term of Sirex juvencus." 



In another article, Edward mentions the fact of a 

 Spider (Aranea domestica) having lived in one of his 

 sealed-up cases for twelve months without food. He 

 had before written to his reverend friend on the 

 subject, but Mr. Smith informed him that he had no 

 books on Entomology, and could give him no informa- 

 tion. Edward says of his spider, that after the case had 

 been sealed up, he saw him walking over the birds con- 

 tained there, until at last he became stationary in one 

 of the corners. " Towards noon of the second day of 

 his incarceration, he commenced operations, and by 



