LETTER II. 



THE MOLLUSCA CONSIDERED AS HURTFUL ANIMALS. 



It is natural to conclude, that if the snail and oyster fairly 

 represent the class, man can have nothing to fear from ani- 

 mals of such limited fticulties and proverbial hebetude ; and 

 while I willingly admit that they have no claim to any bad 

 pre-eminence among his enemies, there are still some noxi- 

 ous species of celebrity among them, whose evil works may 

 occujjy our attention in this letter. 



Of the marine tribes, the Shipworm (Fig. 1, b), is the only 

 one which has attracted much attention ; but the devastation 

 this worm-like Mollusk commits, is sufficiently extensive to 

 have earned for it a hateful notoriety, and justifies the strong 

 language of Linnaeus, when he styles it the " calamitas na- 

 vium." It has been gifted with the power of boring into 

 wood, and while following this instinct, and working out the 

 plans of Providence in removing wrecks and obstructions 

 which have been carried to the ocean, ships, piers, and bul- 

 warks are equally obnoxious to it, and by drilling them in 

 every direction, they soon become unable to resist the vio- 

 lence of the waves, and are washed away. The amount of 

 the damage which the Teredo thus inflicts on marine pro- 

 perty is ciifficult to calculate ; that it is very considerable is 

 proved by the complaints made of the mollusk in almost all 



