[Illustration: DOG-FISH.]
The Dog-fish, which sometimes attains the length of between three and
four feet, is exceedingly voracious. It feeds upon other fish, of which
it destroys great quantities; it does not hesitate to attack the
fishermen, and especially bathers in the sea. It places itself in
ambush, like the Raias, in order to attack its prey.
The flesh of the Dog-fish is hard, smells of musk, and is rarely eaten;
but the skin becomes an article of commerce, and is known as shagrin,
being, like the skin of the Shark, used for making spectacle-cases and
for other ornamental purposes, for which its green color and high polish
recommend it.
There is a smaller species than the preceding, which haunts rocky
shores, where it lies in wait for its prey. Its spots are larger and
more scattered, and its ventral fins are nearly square. It feeds on
Molluscs, Crustaceans, and small Fishes.