COLEOPTERA. 8f 



its course towards the body of the tree, devouring the pith, and 

 thereby forming a cylinckical burrow, several inehes in length, 

 in the centre of the branch. Having reached its full size, 

 which it does towards the end of the summer, it divides the 

 branch at the lower end of its burrow, by gnawing away the 

 wood transversely from within, leaving only the ring of bark 

 untouched. It then retires backwards, stops up the end of its 

 hole, near the transverse section, with fibres of the wood, and 

 awaits the fall of the branch, which is usually broken off and 

 precipitated to the ground by the autumnal winds. The leaves 

 of the oak are rarely shed before the branch falls, and thus 

 serve to break the shock. Branches of five or six feet in length 

 and an inch in diameter are thus severed by these insects, a 

 kind of pruning that must be injurious to the trees, and 

 should be guarded against if possible. By collecting the 

 fallen branches in the autumn, and burning them before the 

 spring, we prevent the development of the beetles, while we 

 derive some benefit from the branches as fuel. 



It is somewhat remarkable that, while the pine and fir tribes 

 rarely suffer to any extent from the depredations of caterpillars 

 and other leaf-eating insects, the resinous odor of these trees, 

 oflensive as it is to such insects, does not prevent many kinds 

 of borers from burrowing into and destroying their trunks. 

 Several of the Capricorn-beetles, while in the grub state, live 

 only in pine and fir trees, or in timber of these kinds of wood. 

 They belong chiefly to the genus CaUidium, a name of un- 

 known or obscure origin. Their antennaB are of moderate 

 length ; they have a somewhat flattened body ; the head nods 

 forward, as in Stenocorifs ; the thorax is broad, nearly circular, 

 and somewhat flattened or indented above; and the thighs are 

 very slender next to the body, but remarkably thick beyond 

 the middle. The larva? are of moderate length, more flattened 

 than the grubs of the other Capricorn-beetles, have a very 

 broad and horny head, small but powerful jaws, and are pro- 

 vided with sLx extremely small legs. They undermine the 

 bark, and perforate the wood in various directions, often doing 

 immense injury to the trees, and to new buildings, in the lum- 

 ber composing which they may happen to be concealed. Their 



