INDIRECT INJURIES CAUSED BY INSECTS. 137 



sapwood, in which its eggs had probably been deposited before the wood 

 was worked up. 1 Of one of the timber-eating beetles (Anobium pertinax) 

 Linne complains " terebravit et destruxit sedilia mea;" 2 and I can renew 

 the same complaint against A. striatum, which not only has destroyed my 

 chairs, but also picture-frames, and has perforated in every direction the 

 deal floor of my chamber, from which it annually emerges through little 

 round apertures in great numbers. The utility of entomological knowledge 

 in economics was strikingly exemplified when the great naturalist just 

 mentioned, at the desire of the King of Sweden, traced out the cause of 

 the destruction of the oak-timber in the royal dock-yards ; and, having 

 detected the lurking culprit under the form of a beetle (Lymexylon navale), 

 by directing the timber to be immersed during the time of the metamor- 

 phosis of that insect and its season of oviposition, furnished a remedy 

 which effectually secured it from its future attacks. 3 No Coleopterous 

 insects are more singular than those that belong to the genus Paussus L. ; 

 and one of them, at least, remarkable, it is said, for emitting a phosphoric 

 light from the globes of its antennae, is also a timber-feeder 4 ; and the genus 

 Trypoxylon, many species of Crabro, Eumenes parietum, Latreille's genera 

 Xylocopa, Chelosloma, Heriades, Megachile, and Anthrophora (all separated 

 from Apis L.), perforate posts and rails and other timber, to form cells for 

 their young. 5 



The Linnean order Aptera furnishes another timber-eating insect, a kind 

 of wood-louse (Limnona terebrans of Dr. Leach), which though scarcely 

 an eighth of the size of the common one, in point of rapidity of execution 

 seems to surpass all its European brethren, and in many cases may be pro- 

 ductive 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 favoured by Charles Lutwidge, Esq. of Hull, 

 with specimens of wood from the piers at Bridlington Quay, which wofully 

 confirm the fears entertained of their total ruin by the hosts of these pigmy 

 assailants that have made good a lodgment in them, and which, though 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 which constitutes their 

 food into a state resembling honeycomb. One specimen was a portion of 

 a three-inch fir plank nailed to the North Pier about three years before, 

 which is crumbled away to less than an inch in thickness in fact, de- 

 ducting the space occupied by the cells, which cover both surfaces as 

 closely as possible, barely half an inch of solid wood is left ; and though 

 its progress is slower in oak, that wood is equally liable to be attacked by 

 it. 6 If this insect were easily introduced to new stations, it might soon 

 prove as destructive to our jetties as the Teredo navalis to those of Holland, 

 and induce the necessity of substituting stone for wood universally, what- 



1 Guerin-Meneville, Revue Zoolog. 1840, p. 151. 2 Syst. Nat. 565. 2. 



5 Smith's Introduction to Botany, Pref xv. 



4 Afzelius in Linn. Trans, iv. 261. 



5 Kirby, Man. Ap. Ang. i. 152. 194. Latreille, Gen. iv. 161. 



6 See the elaborate memoir of Mr. Coldstream in Edin. New Phil. Journ. April, 

 1834 ; remarks on this insect by the Rev. F. W. Hope in Trans. Ent. Soc. Lend. i. 

 119. ; also by Dr. Moore, in Mag. of Nat. Hist. N. S. ii. 206., who states that its in- 

 jurious effects have been known at least forty years in the harbour at Plymouth, 

 where it is called the " gribble." 



