THE FLOSCULES. 
163 
and actually intruded into its disk ; yet it was not till after 
several seconds that the Floscule, perhaps taken aback at 
the insult and deprived for the moment of its presence of 
min d., contracted itself. Presently it did, however, and that 
vigorously, when the rush of inflowing water carried the 
unprepared PleurotrocJta before it, quite into the tube. Here 
it began to make efforts to regain liberty ; yet not, as might 
have seemed obvious, by the way it had entered, but through 
the side of the case. His pushings showed that this was thin, 
soft, and flexible, though sufficiently tough to resist his efforts, 
till at last he found his way out by the regular road. 
The case is doubtless, as with Stephanoceros, an excretion 
thrown off from the skin, and moulded to its cylindrical form 
by the movements of the body on the foot-base, as a pivot. 
The Nutritive System. — The long bristles do not appear to 
have any power of forming currents in the water, not even in 
that subordinate degree which we have seen exercised by the 
Stephanoceros, in maintaining a sort of vortical prison, in which 
the victims are kept in ward. Yet there is a distinct vortex in 
the disk of the Floscule, and minute organisms are drawn into 
it from a considerable distance, and whirled round and round 
till they are swallowed. On the admixture of carmine or 
indigo with the water in the live-box, there is seen within 
the concavity of the disk a vortex, which takes an oval form, 
the longer diameter of which is perpendicular, and whose plane 
is from right to left of the animal. 
The whole of the upper part of the body is lined with a very 
sensitive, contractile, partially-opaque membrane, which, a little 
below the disk, recedes from the walls of the body, and forms a 
diaphragm with a highly contractile and versatile central orifice. 
At some distance lower down another diaphragm occurs, and 
the ample chamber thus enclosed forms a kind of crop, or 
receptacle for the captured prey. Below the second diaphragm 
is another capacious chamber, which we must consider as a 
stomach, since digestion evidently commences in it, and it opens 
into the intestine. 
The mastax, or bulb which ordinarily incloses the jaws,* is 
wholly wanting : the dental apparatus, which is very small, 
evidently springing from the common wall of the stomach, just 
below the second diaphragm. That this absence of the mastax 
is real, and not illusive, is proved by the facts that the Infusoria 
swallowed pass into the stomach, where they accumulate in its 
wide cavity; that the jaws are seen to act on one and another, 
according as they come within reach ; and that after such action 
they pass off again into the same cavity, to undergo another 
* See pp. 34 and 35, notes, 
