WATERS OP WESTEEN INDIA. 35 



Naturalist than I am to distinguish him from the same. The shell 

 is long, oval at one end, and at the other tapering off into a sort of 

 duck-bill shape. The heavy end is covered with toothed ridges, 

 and although, at a glance, the whole shell appears to be one of the 

 most delicate and fragile of the Coast (the thin parts are translucent), 

 an attempt lo scratch it with a penknife shows that it is of very 

 hard stuff. 



To borrow for an instant the special slang of the Mineralogists, 

 most sea-shells are of something like Calcite, but the Piddock and 

 his breed house themselves in Arragonite, a very much harder form of 

 lime. Such a statement, of course, requires to betaken with a good 

 deal of allowance for a " allotropism " ; and other Mineralogical 

 and Chemical details that would be out of place here; but in the 

 main it is as true as that horses are shod with wrought iron and 

 "jumpers*' with steel. "Jumpers," be it known to any reader that 

 didn't know it before, are tools like crowbars, used for boring holes 

 in stones; and of the same use is the shell of the Pholads. 



The " Piddock" himself, though the chief of the family, is not 

 its most active member; piercing chiefly clay and chalk or such 

 comparatively soft substances. He looks, too, like a shell-fish, has 

 the regular two valves of the Conchifera, (there are really five 

 plates, but three are inconspicuous) and nothing very striking 

 about him at first sight, except that fully half of him, the foot, is as 

 transparent as ice. He works like an awkward boy beginning to 

 use boring tools; by half turns right and left; blowing out his 

 sawdust at intervals ; if one may use such a word where the 

 respiratory medium is water. 



As we proceed with this family, we find, in some, the bivalve shell 

 little more than rudimentary, not covering more than one-twentieth 

 part of the animal. This is the case with the Teredos or ship-worms ; 

 so-called because at first sight they look a good deal more like 

 worms than " shell-fish." In^others the shell has four or five valves, 

 easily distinguished, and covering the whole, or most, of the animal. 



Speaking generally, the long " ship-worms," work with the grain 

 of the wood that they attack. They line their tunnels with concrete, 

 and have a sort of miner's law amongst themselves, in virtue 

 whereof they never invade each other's " claims." They usually 

 bore in wood, sometimes in mud. The mud-boring species have 

 been lately sufficiently dealt with by another member of this 

 society, under the name of Kuphus. 



