32 THOUGHTS ON ANIMALCULES. 



VII. 



THE POLYGASTRIA, OR ANIMALCULES WITH MANY 

 STOMACHS. 



The Polygastria, {many stomachs), as the name im- 

 ports, are characterised by having a digestive organ, 

 which, instead of being a single pouch or cavity, as in 

 the Hydra, is composed of numerous little globular 

 bladders, {sacs, or sacculi), connected together by one 

 common tube ; and these clear globular cells or stomachs, 

 receive and assimilate the nutriment when in a suffi- 

 ciently molecular or divided state. From the trans- 

 parency of the bodies of the animalcules, the cells, when 

 filled with coloured food, are easily distinguished, as we 

 shall presently prove by an interesting experiment. 



The Polygastria present great diversity of figure; 

 their movements are performed by the cilia, which are 

 distributed over the body; they increase either by 

 spontaneous division, or by gemmules or buds. Tliis 

 class comprises the minutest forms of animal life hitherto 

 reached by the most powerful microscope. Some kinds 

 (JSIonas vibrio) do not exceed one three-thousandth of a 



