INTESTINAL WORMS. 



117 



of the human body, there 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 Acephalocystis, is peculiar. That kind most fre- 

 quently found in the human subject develops buds or 

 gemmcB from the internal surface, which grow into globular 

 sacs, and at length separate themselves and float at liberty 

 in the fluid of the 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 ? A very eminent 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, 4.5 (Edit. L). 



