Marine Insects Destroyers of Wood. 341 



** Marine Insects destroyers of Wood *. '*' 



» « « « u J }jave already described some of those marine ani- 

 mals, which, by destroying the surface of stones, oblige us to re- 

 pair our harbour-sluices, and other works of the same kind. Let 

 us now attend to those which perforate, nearly in the same man- 

 ner, all sorts of wood. For a long time it had been the prac- 

 tice at Havre, to keep the fir-logs, of which masts are made for 

 the ships of war, in a basin called La Bare-floride. Some years 

 ago, it was observed that the surface of these logs was destroyed 

 by marine insects, which had bored in the softest parts to the 

 depth of an inch and a half, so that the diameter of each log 

 was diminished by three inches : it was feared that the timber, 

 being gradually softened by the action of the sea, would be en- 

 tirely destroyed by these insects, or at least rendered useless. I 

 know not whether any other measure was taken to remedy this 

 evil ; but soon after it was discovered, the Bare-floride was aban- 

 doned, and the logs removed to the ditches of the fortifications, 

 and to another basin, where the mast-yard now is. Having 

 heard, by chance, some time after the removal of the masts, of 

 this destruction of such valuable materials, I sought for the ene- 

 my secretly, in places to which I had greater freedom of access 

 than to the dockyard, and I discovered an old fishing-station 

 which was infested by it, where ash, elm, and even oak, had long 

 before been attacked, and in which the animals could be brought 

 to view by removing the surface of the wood. I took a few 

 from their holes, and placed them in sea-water, on different 

 kinds of wood, recently cut. They lodged themselves in these 

 within twelve hours. I had then no doubt of these being the 

 agents in the destruction of the mast-timber. The animal is 

 semicylindrical in form, or nearly so, covered with a scaly crust, 

 divided unequally into fourteen segments, of which the largest 

 are near the head, the smallest towards the tail, which is trun- 

 cated, and perforated by the anus. The head is rounded, and 

 terminated beneath by a kind of blunt beak, which, apparently, 

 serves the animal in boring the wood, as it inserts its head first, 

 and the debris which it forms passes between its feet under its 

 belly. This debris sometimes covers the back under the form 



• Extract from a paper entitled, " Extraits du portefeuille de M. I'AbW 

 Dicquemarc ; Insects marines, destructeurs des bois." 



