ATTEMPT TO RE-CLASSIFY THE ROTIFERS. 337 



Nothing could be more precise, or more symmetrical ; but 

 these merits — dear as they are to most men, and to all 

 classifiers — have been purchased at the expense of grievous 

 faults. 



In the first place, there is not a truly loricated animal at all 

 in the whole of the Monotrocha. They are all soft-bodied, 

 flexible Rotifers, and the great majority live in gelatinous 

 tubes secreted from their own skins, and strengthened by the 

 adherence to them of foreign bodies. To give such cases the 

 same name as that chosen for the transparent chitinous 

 carapace of a Brachionus (fig. 7) is surely an absurdity. 



In the next place, the division Holotrocha does not 

 really exist. For rejecting Icthydium and Chsetonotus 

 as not being Rotifers at all, as well as the very doubtful 

 genus Glenophora, the remaining three genera, viz. CEcis- 

 tes, Conochilus, and Ptygura have all gaps in their 

 large ciliary circle precisely as Melicerta (fig. 9) has. The 

 gap is easily seen in Conochilus, and lies on one side of the 

 antennae, while the mouth is on the other; and in CEcistes, 

 although the gap in the ciliary wreath is small and rather 

 difficult to be made out (unless the animal is fortunately 

 placed), still it is there; and it is on the ant-oral side just as 

 it is in Melicerta (fig. 9). 



Again it is surely a confusing of very unlike things to 

 speak of the nearly motionless setae of Stephanoceros 

 (fig. 10) and Floscularia (fig. 11) (often in the latter 

 stretching to the animaFs full length) in the same terms as 

 those applied to the ciliary wreath of Melicerta (fig. 9). 

 There is no sort of similarity between them ; and nothing but 

 the exigencies of a symmetrical system could have led to such 

 a misuse of names. 



Strictly speaking too the term Monotrocha is as mis- 

 leading as any that we have already considered ; for nearly all 

 the genera included in this group have not one ciliary wreath, 

 but two, running parallel to each other — one of large cilia, and 

 one of small ones, with the mouth lying between the two. 



Nor is this all. The sub-division into genera is made to 



