supporting lamella
supporting lamella
supporting lamella
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526 W. B. HAEDY.<br />
inserted through the mouth, injected a drop of sea water containing<br />
the one in suspension or the other in solution. Later,<br />
however, I was more fortunate, and succeeded in obtaining<br />
specimens with food in the enteric cavity. In one case the<br />
prey was a Crustacean of some considerable size, so that it<br />
produced a very obvious bulging of the animal. I did not<br />
witness the capture and ingestion of the prey, but the specimen<br />
was killed before the digestive fluid had produced any change<br />
in the tissues. Fig. 21 is taken from this specimen. It also<br />
contained the remains of a previous meal in the lower part of<br />
the enteric space. Other specimens furnished other stages,<br />
and in this way, as a result of an examination of a large number<br />
of animals, I was enabled to obtain a series representing, to a<br />
certain extent, the various stages of digestion.<br />
Myriothela is carnivorous, and captures small Crustacea.<br />
In one case the meal consisted of a half-digested egg, either<br />
derived from the gonophores of the individual in question, or<br />
from those of its neighbours. 1<br />
Digestion is carried on at first in the lower portion of the<br />
tentacle-bearing region—that is, in that region where the<br />
gland-cells are most abundant, and results in a disintegration<br />
of the prey, brought about by the agency of the digestive<br />
fluid.<br />
The gland-cells which first discharge their contents are<br />
those in the immediate neighbourhood of the meal, but even<br />
there all the cells are not affected at once, those which are<br />
most loaded with granules probably being discharged first.<br />
Some of the gland-cells in the proximal region of the blastostyles<br />
and in the foot may be found undischarged until nearly<br />
1<br />
The huge yolk-laden eggs, when set free from the gonophores, are taken<br />
by tentacle-like bodies, the "claspers," which hold them while development<br />
proceeds and until the actinula larva is fully formed. In March and April, however,<br />
the claspers are not always present, and the eggs formed then when ripe<br />
are shed and sink to the bottom, where they become attached. I think that<br />
further research will show that these early eggs have a more direct development<br />
than those formed later, and pass at once to the form of the adult without<br />
the intervention of the free-swimming actinula stage. It was one of these<br />
free eggs which apparently had found lodgment in the enteric cavity.