INDIRECT INJURIES CAUSED BY INSECTS. 137 
sapwood, in which its eggs had probably been deposited before the wood 
was worked up.*_ Of one of the timber-eating beetles (Anobium pertinax) 
Linné complains “ terebravit et destruvit sedilia mea;”? 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. 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 antennzg, is also a timber-feeder* ; and the genus 
Trypoxylon, many species of Crabro, Eumenes parietum, Latreille’s genera 
Xylocopa, Chelostoma, Heriades, Megachile, and Anthrophora (all separated 
from Apis L.), perforate posts and rails and other timber, to form cells for 
their young.° 
The Linnean order Aptera furnishes another timber-eating insect, a kind 
of wood-louse (Limnoria 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 crambled 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.° 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 Gucrin-Méneville, Revue Zoolog. 1840, p. lol. 2 Syst. Nat. 565. 2, 
5 Smith’s Zntroduction to Botany, Pref xv. 
4 Afzelius in Linn. Trans, iv, 261. 
5 Kirby, Mon. Ap. Ang. i, 152. 194. Latreille, Gen. iv. 161—. 
® See the elaborate memoir of Mr. Coldstream in Juin. New Phil. Journ. Apvil, 
1834; remarks on this insect by the Rey. F. W. Hope in Trans. Znt. Soc. Lend. i. 
119.5 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.” 
