All these statements may be verified in the
case of the purple murex and the ceryx by observation within the whorl
of the shell. What comes next to the oesophagus is the gut; in fact,
the gut is continuous with the oesophagus, and runs its whole length
uncomplicated to the outlet of the residuum. The gut has its point
of origin in the region of the coil of the mecon, or so-called
'poppy', and is wider hereabouts (for remember, the mecon is for the
most part a sort of excretion in all testaceans); it then takes a bend
and runs up again towards the fleshy part, and terminates by the
side of the head, where the animal discharges its residuum; and this
holds good in the case of all stromboid testaceans, whether
terrestrial or marine. From the stomach there is drawn in a parallel
direction with the oesophagus, in the larger snails, a long white duct
enveloped in a membrane, resembling in colour the mastoid formations
higher up; and in it are nicks or interruptions, as in the egg-mass of
the crawfish, only, by the way, the duct of which we are treating is
white and the egg-mass of the crawfish is red. This formation has no
outlet nor duct, but is enveloped in a thin membrane with a narrow
cavity in its interior.
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