ON THE CLASSES OF THE 



logy as deserving a severer epithet than vague, which has 

 been used in order to unite the Entozoa with the Echino- 

 derma. Because some of the Tntestinaux of Cuvier have 

 two fibrous lines, or muscular threads, shooting out from 

 a circle round their mouths, it has been asserted that 

 these animals afford traces of a radiated structure; but 

 other naturalists appear to have drawn from the same 

 observation a much more correct conclusion, in con- 

 ceiving that these two fibres, where they exist, are but 

 modifications of the ordinary nervous system of the An- 

 nulosa, allowance being made for their being animals far 

 more imperfect than the usual types of this system of 

 construction. It seems indeed impossible in an arrange- 

 ment which has any pretensions to being natural, to sepa- 

 rate some of the Entozoa, such as the Nematoidea of 

 Rudolf], far from Eumbricus and Gordius. 



With respect to this new division of animals, which I have 

 called Acrita, the following definition, which is nearly that of 

 Lamarck, will serve to exclude such of the Intestinaux of 

 Cuvier as deserve a higher place in the scale of nature. 



Animalia gelatinosa pohjmorplia, interaneis nidlis me- 

 dullaque indistincta. 



Os interdum indistinctum, sed nutritio absorptione ex- 

 terna vel interna semper sistit. Anas nidlus. 



Reproductio fissipara vel gemmipara, gemmis modo ex- 

 tends modo internis, interdum acervatis. 



Pleraqueex individuis pluribus semper coharentibus ani- 

 malia composita sistunt.- 



The distinctive character of these animals is therefore 

 principally negative as referred to animals, and positive 

 as referred to plants. The simple texture of their cellular 

 tissue is common to them with the Algee; their gemmipa- 



