238 INDIRECT INJURIES CAUSED BY INSECTS. 



several specimens of S. Gigas were seen to come out of 

 the floor of a nursery in a gentleman's house, to the no 

 small alarm and discomfiture of both nurse and children^. 

 — The genus Tri/poxijlon^ many species of Crabro, Eu- 

 mencs Parietum, Latreille's genera Xylocopa, Chelostoma, 

 Heriades^ Megachilc and Anthophora^ (all separated from 

 Apis J L.,) perforate posts and rails and other timber, to 

 form cells for their young ^. 



The Linnean order Aptcra furnishes another timber- 

 eating insect, a kind of wood-louse, though scarcely an 

 eighth of the size of the common one, {Limnoria tere- 

 brans of Dr. Leach,) which in point of rapidity of exe- 

 cution seems to surpass all its European brethren, and 

 in many cases may be productive of more serious injury 

 than any of them, since it attacks the wood-work of piers 

 and jetties constructed in salt-water, and so effectually, 

 as to threaten the rapid destruction of those in which it 

 has established itself. In December 1815 I was fa- 

 voured by Charles Lutwidge, esq. of Hull, with speci- 

 mens of wood from the piers at Bridlington Quay which 

 wofully confirm the fears entertained of their total ruin 

 by the hosts of these pygmy assailants that have made 

 jrood a lodgement in them, and which, thoui>h not so 

 big as a grain of rice, ply their masticatory organs with 

 such assiduity as to have reduced great part of the wood- 

 work into a state resembling honey-comb. One speci- 

 men was a portion of a three-inch fir plank nailed to 

 the North Pier about three years since, which is now 

 crumbled away to less than an inch in thickness — in fact, 

 deducting the space occupied by the cells which cover 



» Linn. Trans. X. 403. 



" Kirby, Man. Ap. Aug. i. 153-194. Latreille, Gen. iv. 161—. 



