78 INSECTS INJURIOUS TO VEGETATION. 



however, fly by day, and may be found on flowers, feeding on the 

 pollen and the blossoms. When annoyed or taken into the hands, 

 they make a squeaking sound by rubbing the joints of the thorax 

 and abdomen together. The females are generally larger and 

 more robust than the males, and have rather shorter antennae. 

 Moreover they are provided with a jointed tube at the end of the 

 body, capable of being extended or drawn in like the joints of a 

 telescope, by means of which they convey their eggs into the 

 holes and chinks of the bark of plants. 



The larvse hatched from these eggs are long, whitish, fleshy 

 grubs, with the transverse incisions of the body very deeply 

 marked, so that the rings are very convex or hunched both above 

 and below. The body tapers a little behind, and is blunt-pointed. 

 The head is much smaller than the first ring, slightly bent down- 

 wards, of a horny consistence, and is provided with short but very 

 powerful jaws, by means whereof the insect can bore, as with a 

 centre-bit, a cylindrical passage through the most sohd wood. 

 Some of these borers have six very small legs, namely, one pair 

 under each of the first three rings ; but most of them want even 

 these short and imperfect limbs, and move through their burrows 

 by the ahernate extension and contraction of their bodies, on each 

 or on most of the rings of which, both above and below, there is 

 an oval space covered with little elevations, somewhat like the 

 teeth of a fine rasp ; and these little oval rasps, which are de- 

 sio-ned to aid the grubs in their motions, fully make up to them the 

 want of proper feet. Some of these borers always keep one end 

 of their burrows open, out of which, from time to time, diey cast 

 their chips, resembling coarse saw-dust ; others, as fast as they 

 proceed, fill up the passages behind them with their castings, well 

 known here by the name of powder-post. These borers five from 

 one year to three, or perhaps more years before they come to 

 their growth. They undergo their transformations at the furthest 

 extremity of their burrows, many of them previously gnawing a 

 passage through the wood to the inside of the bark, for their future 

 escape. The pupa is at first soft and whitish, and it exhibits all 

 the parts of the future beetle under a filmy veil which inwraps 

 every limb. The wings and legs are folded upon the breast, the 

 long antenna are turned back against the sides of the body, and 



