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. The
mouth in the Cephalopoda is succeeded by a long gullet. This leads
to a crop, like that of a bird, and directly continuous with this is
the stomach, from which a gut runs without windings to the vent. The
Sepias and the Poulps resemble each other completely, so far as
regards the shape and consistency of these parts. But not so the
Teuthides (Calamaries). Here, as in the other groups there are the two
stomach-like receptacles; but the first of these cavities has less
resemblance to a crop, and in neither is the form [or the consistency]
the same as in the other kinds, the whole body indeed being made of
a softer kind of flesh.
The object of this arrangement of the parts in question is the
same in the Cephalopoda as in Birds; for these also are all unable
to masticate their food; and therefore it is that a crop precedes
their stomach.
For purposes of defence, and to enable them to escape from their
foes, the Cephalopoda have what is called their ink. This is contained
in a membranous pouch, which is attached to the body and provided with
a terminal outlet just at the point where what is termed the funnel
gives issue to the residua of the stomach. This funnel is placed on
the ventral surface of the animal. All Cephalopoda alike have this
characteristic ink, but chief of all the Sepia, where it is more
abundant than in the rest. When the animal is disturbed and frightened
it uses this ink to make the surrounding water black and turbid, and
so, as it were, puts a shield in front of its body
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