Is one of the most curious creatures of "the watery kingdom." It is
popularly termed a fish, though it is, in fact, a worm, belonging to
the order termed _Mollusca, (Molluscus_, soft,) from the body being of
a pulpy substance and having no skeleton. It differs in many respects
from other animals of its class, particularly with regard to its
internal structure, the perfect formation of the viscera, eyes, and
even organs of hearing. Moreover, "it has three hearts, two of which
are placed at the root of the two branchiae (or gills); they receive
the blood from the body, and propel it into the branchiae. The
returning veins open into the middle heart, from which the aorta
proceeds."[7] Of Cuttle-fish there are several species. That
represented in the annexed Cut is the common or officinal Cuttle-fish,
(_Sepia officinalis_, Lin). It consists of a soft, pulpy, body, with
processes or arms, which are furnished with small holes or suckers,
by means of which the animal fixes itself in the manner of
cupping-glasses. These holes increase with the age of the animal; and
in some species amount to upwards of one thousand. The arms are often
torn or nipped off by shell or other fishes, but the animal has the
power of speedily reproducing the limbs. By means of the suckers the
Cuttle-fish usually affects its locomotion. "It swims at freedom in
the bosom of the sea, moving by sudden and irregular jerks, the body
being nearly in a perpendicular position, and the head directed
downwards and backwards. Some species have a fleshy, muscular fin
on each side, by aid of which they accomplish these apparently
inconvenient motions; but, at least, an equal number of them are
finless, and yet can swim with perhaps little less agility. Lamarck,
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]