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LETTERS FROM 
we collect ourselves are small and not very 
beautiful, but we have bought a few tolerably 
fine shells of the fishermen, who occasionally 
find them in the baskets which they sink to 
the bottom for the purpose of catching 
crabs. These crab-pots are always set on 
rocky ground, where it is impossible to use 
a dredge, and as we can obtain very few 
shells on the sandy bottom, I conclude they 
prefer the former situation from finding a 
better supply of food there. 
We have been much more successful in 
our search for land-shells, which I think are 
rather plentiful on this island. One very 
curious species, the bulimus decollotus , is 
very common here: the full-grown shells 
have invariably several of the upper coils 
broken off, so that they appear imperfect, 
but the young of this species are not thus 
mutilated. The little left-handed shell, 
