INFUSORIAL ANIMALCULES. 59 



easy to satisfy ourselves that they do not open on the 

 exterior. Similar cavities are formed in the mucus of 

 true cellular plants, particularly in certain aquatic 

 Oryptogamia. 



" My botanical labours prevent me from carrying these 

 researches farther, but enough has been said to induce the 

 naturalist to pursue them. They require a great degree 

 of perseverance, for it is not easy to establish these 

 facts in all Infusoria, but they are of high importance, 

 since the order Polygastrica has already been admitted 

 into many modern treatises on Zoology." — {Ed. Phil. J. 

 vol. xxviii.) 



Besunid of " Du Jarclin sur les Infu.soires dans Its Annales 

 des Sciences Naturelles." 



" The Infusoria (leaving out of the question the 

 Systolides or Rotateurs, which are much more elevated 

 in the scale of animals, and the Bacillaria, which, along 

 with the Closteria, are more nearly related to the vegetable 

 kingdom) have their origin, for the most part, from un- 

 known germs, in artificial and natural infusions, stagnant 

 water, and rivers, or such portions as rest over vegetable 

 remains — no other mode of propagation, except self- 

 division, being well ascertained. The fleshy substance of 

 their bodies is dilatable and contractile, like the muscular 

 flesh of the superior animals, but present no absolute trace 

 of fibres or membrane, appearing, on the contrary, 



