THE TIMBER CAPRTCOTIN. 251 



Changes Fly only at night. 



where it attains its full size. It first proceeds in 

 a serpentine direction, filling the space which it 

 leaves with its excrement, resembling saw-dust, 

 and stopping all ingress to enemies from without. 

 When it has arrived at its utmost dimensions, it 

 does not confine itself to one direction, but works 

 in a kind of labyrinth, eating backwards and for- 

 wards, which gives the wood under the bark a 

 very irregular surface: by this means its paths 

 are rendered of considerable width. The bed of 

 its paths exhibits, when closely examined, a cu- 

 rious appearance, occasioned by the erosions of 

 its jaws, which excavate an infinity of little rami- 

 fied canals. When the insect is about to assume 

 its chrysalis state, it bores down obliquely into 

 the solid wood, to the depth sometimes of three 

 inches, and seldom, if ever, less than two. These 

 holes are nearly semi-cylindrical, expressing ex- 

 actly the form of the grub. 



The larvae are destitute of feet, pale, folded, 

 somewhat hahy, convex above, and divided into 

 thirteen segments. Their head is large and con- 

 vex. Some of the larvae are hatched in Octo- 

 ber; and it is supposed that about the beginning 

 of March they assume their chrysalis state. At 

 the place in the bark, opposite to the hole from 

 whence they descended into the wood, the per- 

 fect insects gnaw their way out, which generally 

 takes place betwixt the middle of May and the 

 middle of June. These insects are supposed to 

 fly only in the night, but during the day they 



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