supporting lamella
supporting lamella
supporting lamella
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582 W. B. HARDY.<br />
from the results of digestion in the enteric cavity. The fate<br />
of sodium sulphindigotate when introduced into the enteric<br />
cavity is interesting in this connection, for though a considerable<br />
portion of that pigment is rapidly decolourised, some may<br />
be found after a short period in the vacuolate cells associated<br />
with the nutritive spheres in the various stages of their formation<br />
in such a way that these bodies are tinged with blue in<br />
irregular patches. We may conclude, therefore, that the substances<br />
resulting from the solution of the tissue of the prey<br />
are mainly absorbed by the vacuolate cells, while at the same<br />
time ingestion of disintegrated fragments, possibly of a resistent<br />
nature, takes place to a limited extent, and is carried<br />
on by the apical cells of the villi in the middle region of the<br />
body. And the distribution of the products of digestion to<br />
the more remote portions of the endoderm is effected by the<br />
agency of the general somatic fluid.<br />
But, as I said before, there are reasons for believing that<br />
the somatic fluid is more than a vehicle for the distribution of<br />
the immediate results of digestion. Let us now turn to a<br />
consideration of those reasons.<br />
In the blastostyles the extensive accumulation of nutritive<br />
spheres is in obvious relation to the active and important processes<br />
carried on in those structures. But the nutritive<br />
spheres are stored in equal abundance in the endoderm of the<br />
foot, where, during the summer and autumn, there appears to<br />
be no great call for this enormous reserve of nutritive material.<br />
On the other hand, throughout the whole tentacular<br />
region and usually in the endoderm of the tentacles themselves<br />
no abundant reserve of food-stuff is present. It is, as I<br />
pointed out above, highly doubtful whether the peculiar bodies<br />
sometimes found in the endoderm of the tentacles are of the<br />
nature of simple reserve nutriment. On the other hand, it is<br />
equally certain that the actively motile and sensitive tissues<br />
of the tentacular and oral regions are not supplied directly<br />
and solely from the immediate products of digestion. We are,<br />
therefore, compelled to conclude that the nutritive material<br />
stored in one region of the body may be conveyed as occasion