606 



SYSTEMATIC HISTORY OF THE INFUSOEIA. 



The genera are distributed as follows : — 



Surface of 

 body desti- 

 tute of Yl-i 

 bratile 

 cilia .... 



Direct 

 truncated 

 mouth 

 (no lip) . . 



^ Yibratile f Body simple Enchelys. 



cilia at the < 



mouth ... I Body double Disoma. 



Eay-like 

 tentacula 

 not yibra- 

 tile 



r The body co-U^^.^^^^j 

 Stalkless ^eredwithraysj 



\ Eays at the edge Trichodiscus. 

 ^ Stalked Podophrya. 



No neck Trichoda. 



Oblique 

 truncated 



i rrflip) I With neck Lacrymaria. 



Sm-face of 

 body with 

 vibratile 

 (^ cilia _ 



Oblique truncated mouth, with lip Leucophrys. 



Direct truncated mouth, no lip Holoplu*ya. 



Teeth present Prorodon. 



In the arrangement of Dujardin, and under his fom^th order — comprehend- 

 ing '^ ciliated Infusoria without a contractile integument, and with or without 

 a mouth " — a family having a similar name, Enchelina (Enchelyens, so- 

 caUed after a genus Enchelys) is instituted. But, most unfortunately for 

 science, this family and this genus, with respect to the animalcules they 

 include, in no way correspond with the similarly-named family and genus 

 of Ehrenberg. This is remarked by Dujardin himself ; and he adds, with 

 reference to the genus EiicJiehjs (Ehr.), that, in the whole course of his ob- 

 servations, he never met Avith any Infusoria bearing the characters attributed 

 by Ehrenberg to that genus, and he is led to conclude that the beings intended 

 are Paramecia with a terminal mouth, or else Bursarice imperfectly examined, 

 and the cilia of the sui'face overlooked. 



The family Enchelina is thus briefly characterized by Dujardin : — " Animals 

 partially or entirely covered with cilia, dispersed over the sui'face irregularly ; 

 mouth wanting." 



The family Cyclidina (Ehr.) seems, indeed, much more nearly allied to the 

 Enchelys of Dujardin ; but its characters, as given by Ehrenberg, are not 

 sufficiently definite to attempt an identification. 



Stein severely blames Dujardin for the transposition of generic names he 

 has been guilty of in the case of this genus and Cyclidium ; for, as he justly 

 observes, it is a proceeding productive of confusion and error. The Enchelys 

 noclulosa, he adds, is the CycJicUum Glaucoma (Ehr.), and scarcely distin- 

 guishable from E. triquetra (Buj.). Acomia Ovulmn seems nothing else than 

 Cyclklium Glaucoma, and Uronema marina another closely-allied form, and, 

 liiie Glaucoma itself, the embryo of some other animalcule. The three 

 remaining species of Enchelys enumerated by the French writer, viz. E. cor- 

 rugata, E. subangulata, and E. ovata, are so imperfectly observed as to be 

 worthless, and their union in the same genus with Glaucoma quite unwar- 

 rantable. 



Yet, if Dujardin has proceeded very incautiously in rejecting the En- 

 chelia of Ehrenberg and in redistributing its genera, no apologist of the 

 BerHn naturalist would contend that it should be left as it is; for every 

 person having any acquaintance with the beings brought together as En- 

 chclia Aivill be struck with their heterogeneous characters. ActbiophrySf 



