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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