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ck, indeed, denies this, and says that these can only trail themselves along the bottom by means of the suckers. This is probably their usual mode of proceeding; that it is not their only one, we have the positive affirmation of other observers."[8] Serviceable as these arms undoubtedly are to the Cuttle-fish, Blumenbach thinks it questionable whether they can be considered as organs of touch, in the more limited sense to which he has confined that term.[9] THE CUTTLE-FISH. [Illustration: The Cuttle-fish.] The jaws of the Cuttle-fish, it should be observed, are fixed in the body because there is no head to which they can be articulated. They are of horny substance, and resemble the bill of a parrot. They are in the centre of the under part of the body, surrounded by the arms. By means of these parts, the shell-fish which are taken for food, are completely triturated. [7] Cuvier. [8] Nat. Hist. Molluscous Animals, Mag. Nat. Hist. vol. iii. p. 527. [9] Manual Comp. Anat. p. 263. We now come to the most peculiar parts of the structure of the Cuttle-fish, viz. the _ear and eye_, inasmuch as it is the only animal of its class, in which any thing has hitherto been discovered, at all like an organ of hearing, or that has been shown to possess true eyes.[10] The ears consist of two oval cavities, in the cartilaginous ring, to which the large arms of the animal are affixed. In each of these is a small bag, containing a bony substance, and receiving the termination of the nerves, like those of the vestibulum (or cavity in the bone of the ear) in fishes. The nature of the eyes cannot be disputed. "They resemble, on the whole, those of red-blooded animals, particularly fishes; they are at least incomparably more like them than the eyes of any known insects; yet they are distinguished by several extraordinary peculiarities. The front of the eye-ball is covered with a loose membrane instead of a cornea; the iris is composed of a firm substance; and a process projects from the upper margin of the pupil, which gives that membrane a semilunar form."[11] The exterior coat or ball is remarkably strong, so as to seem almost calcareous, and is, when taken out, of a brilliant pearl colour; it is worn in some parts of Italy, and in the Grecian islands by way of artificial pearl in necklaces. [10] In all other worms the eyes are entirely wanting, or their existence is very doubtful. Wh
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