But all these organs, as has
been stated, are distinctly traceable in the larger species, while
in the small ones they are in some cases almost, and in others
altogether, indiscernible. Hence they are most plainly visible in
the large scallops; and these are the bivalves that have one valve
flat-shaped, like the lid of a pot. The outlet of the excretion is
in all these animals (save for the exception to be afterwards related)
on one side; for there is a passage whereby the excretion passes
out. (And, remember, the mecon or poppy, as has been stated, is an
excretion in all these animals-an excretion enveloped in a
membrane.) The so-called egg has no outlet in any of these
creatures, but is merely an excrescence in the fleshy mass; and it
is not situated in the same region with the gut, but the 'egg' is
situated on the right-hand side and the gut on the left. Such are
the relations of the anal vent in most of these animals; but in the
case of the wild limpet (called by some the 'sea-ear'), the residuum
issues beneath the shell, for the shell is perforated to give an
outlet. In this particular limpet the stomach is seen coming after the
mouth, and the egg-shaped formations are discernible.
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