312 ROTIFERA. 



The systematic position of these animals is very uncertain ; indeed, our know- 

 ledge of their anatomy hardly justifies us in coming to a decision on the matter. 

 In the published accounts of their anatomy there is no description of the 

 vascular system, nor is the arrangement of the body-cavity made clear. It 

 would appear, however, that the kidneys and generative organs are not connected 

 with any other space, and it is possible that they are to be regarded as coelomic, 

 as the products of two pairs of coelomic chambers (mesoblastic somites). If this 

 should turn out to be a correct supposition, it would support the view that they 

 are related to Annelids a view which is prompted by the relations and segmenta- 

 tion of the central nervous system. Ecliinodercs Duj. 



