What is a Cuttle Fish ?

A cuttle fish is not a fish. It is a mollusc (fleshy animals without backbones ). It belongs to that class of huge molluscs which are "cephalopods"or "head- footed animals" they are called "head -footed", because of the peculiar formation of these sea -creatures- arrangement of their feet and arm like tentacles which grow around the head and the mouth;and the arm - like tentacles are extensions of their feet. octopus also belongs to this class of molluscs. 

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The cuttle fish has a remarkable characteristic. Its travels silently and smoothly through. the water, moving the row of fins which are pasted to its shield - shaped body.when it moves erects the first pair of its tentacles or feelers and when it comes within the attacking distance of its prey, it suddenly shoots out its two long tentacles from pockets which are placed in its brood head behind its staring bulging eyes. It grasps the victim with suckers which are placed at thee end of these tentacles and then draws it within the reach of four shorter pairs of tentacles, which also have suckers, and are arranged around its head. It had a parrot- like beak. It the victim has a hard shell, it can crush it with the beak if it decides to retreat from an enemy, it backs away quickly by forcing out water through a tube called "siphon" when it wants to discourage the enemy from chasing it, it darkness the water with a massive discharge of an ink-like fluid called "sepia".

source :- The Hindu