544 POLYGASTRIC ANIMALCULES. 



masses already mentioned, as if they floated loosely in the cavity 

 of the Animalcule, and did not form part of the supposed 

 alimentary canal. And it has been found that, when a small 

 quantity of an alkaline solution is allowed to touch their bodies, 

 they burst, and discharge these globules, which seem to have 

 been imbedded in a soft gelatinous substance. Some of the 

 globules appear as if entirely composed of the particles on which 

 the animal has been feeding ; and they have probably derived 

 their globular form, from being moulded (as it were) in a little 

 cavity behind the mouth. They are, for the most part, of very 

 uniform size in the same species of Animalcule. But others 

 have all the character of Cells; and it may be questioned 

 whether they do not perform, in the economy of the Animalcule, 

 the same purposes as the cells which float in the nutritious fluids 

 of higher animals. The whole subject of the nature of the 

 organisation and life of these Animalcules, is still enveloped in 

 great mystery, notwithstanding the extraordinary discoveries of 

 the last few years. Some Physiologists doubt whether the 

 greater number of them are to be regarded in any higher light 

 than as single cells, not possessed of any consciousness or will, 

 and having the same kind of power of movement as that which 

 is possessed by those Epithelium cells which are furnished with 

 cilia, these, when detached from the surface on which they 

 lay, being often seen to move in fluid for many hours. The 

 Author does not at present feel himself able to express a decided 

 opinion upon this interesting question. 



1120. Putting aside the undetermined question of the 

 interior organisation of the digestive apparatus, we may pass 

 to the consideration of other phenomena presented by this 

 remarkable class. Food is usually conveyed to the mouth by 

 the vibration of the cilia which surround it ; in this manner a 

 vortex is produced in the fluid, which brings the particles float- 

 ing in it, or other Animalcules swimming in its neighbourhood, 

 within the grasp of the lips of that aperture. Sometimes even 

 very large substances (in proportion to the size of the individual) 

 are entrapped and swallowed in this manner; many species 

 having much of the voracious character of the Sea-Anemone, 



