INTESTINAL WORMS. 
117 
of the human body, thero are frequently found imbedded 
certain globular bodies of pearly whiteness, varying in size 
from that of a pea to that of a large orange. It is a sim- 
ple bag of membrane, without any orifice or any organs, 
but filled with albuminous fluid. It exhibits no sign of 
life, no feeling, even when touched or irritated ; but 
if pricked, the contained fluid is forcibly spirted out, from 
the elasticity of the membranous walls. 
The increase of this creature, which is known by the 
term Aceplialocystis, is peculiar. That kind most fre- 
quently found in the human subject develops buds or 
gemma from the internal surface, which grow into globular 
sacs, and at length separate themselves and float at liberty 
in the fluid of tho interior. These in turn repeat the same 
process, producing a progeny within themselves, and thus 
successive generations are found to exist, developed one 
•within another, like those hollow toys which represent a 
fruit, and which, on being opened, reveal a smaller of the 
same kind, that another, and another, till the examiner is 
tired of opening. 
Now is this an animal or not 1 A very eminont autho- 
rity, Professor Owen, thinks not. “ It seems to me,” he 
observes, “ to be most truly designated as a ‘ gigantic or- 
ganic cell,’ not as a species of animal, even of the simplest 
kind.”* 
Yet how closely this treads on the heels of the Cysticer- 
cus, such as is often found in vast numbers in the fat of 
swine, communicating to it that appearance which is known 
as “ measly.” It is a bladder in all respects like the pre- 
ceding, except that at one part it is drawn off to a length- 
* Comp. Anat. i. 45 (Edit. i.). 
