OF THE CILIATA. STOMATODA. 571 



in Na'is (one of the Annelida) (xxi. 28, ! supposes this armature replaces the usual 

 29). i fringe of cilia, in the animals after having 



0. uncinata (Schultze). — "Resembles : attained a certain age or stage. In the 

 0. Planariarum in general organization ; interior of Plcmaria Ulva, &c. 1-120". 

 it has the same soi-t of pulsating vessel, O. Tritonis (Pertj^). — Discoid, rounded 

 and a similar nucleus ; it multiplies by in front, wdth a loop-like depression ; 

 transverse fission, and differs from all colourless. 1-336". Revolves on its 

 other known Opalince by having a pair shorter axis. Parasitic in the intestine 

 of strong, homy uncini at the anterior of Triton cnstafus (the crested Water- 

 extremity, one on each side of the median newt). Is very like O. Hananmi, and 

 line, giving it a bilateral character. Stein requires fmther examination. 



O. Nucleus = Bursaria Nucleus ; 0. Entozoon = Bursaria Entozoon ; O. intestinalis 

 = Bursaria intestinalis. These three presumed species are nothing more than 

 different phases of gi'owth and development of Opafina {Bursaria, Ehr.) Ranarum. 

 We have, however, retained the brief notes of their characters as Bursarice given 

 by Ehrenberg. 



FAMILY IT.— COBALINA (Perty). 



Animals parasitic ; either mth or without a mouth ; most of them receive 

 only the juices of other animals. Body mostly flattened, oval, elliptic, or 

 remfoiTQ, T\-ith numerous rows of very delicate cilia, and often with an un- 

 cinate vaiiety on the under surface. An oral-looking depression or fold fur- 

 nished with stronger cilia commonly perceptible ; but several have no such 

 indication of a mouth. Only those living externally upon animals are capable 

 of receiving solid noimshment. In internal functions and in foiTQ they pre- 

 sent a general uniformity and agreement, and are equally peculiar ; they 

 occupy a lower position than free living forms similar to them ; their move- 

 ments are simply automatic in character. 



a. With rows of cilia above, and uncini beneath. 



Genus ALASTOE. — The type of this genus is the Kerona Polyporum 

 (Ehr.), and is called Alastor Polyporimi. 



b. With delicate cilia both above and beneath. Receive only the juices of 



other animals. 

 Genus PLAGIOTOMA(Duj.) (vide Family TuACHELmA). 

 Plagiotoma Lumbrici ; Pl. Concharurn ; Pl. (?) diffoi'mis. 



Genus LEUCOPHRYS (Duj.) {vide ante, p. 570, Opaloa Lumbrici). 

 Leucophhys striata. 



Division B.— STOMATODA. 



FAMILY I.— CYCLIDIXA. 

 (X. 209-212). 



Illoricated Polygastriea devoid of eye-specks and of true alimentary canal, 

 and having but one alimentary aperture, fui-nished \\ith cilia or bristles, the 

 various groupings and relations of which afford characters for the discrimina- 

 tion of the genera ; gastric cells (vacuoles) have been observed in two species 

 of Cyclidium. Locomotion is effected by the \ibratile cilia and a filament 

 proceeding from the anterior extremity. 



The genera are distributed as follows : — 



[ Body compressed — cilia arranged in a single | ^ y-,- 

 Body furnished with ciHa ] circle j " 



1 Body round— cilia scattered all over Pantotrichum. 



Body furnished with bristles Cha?tomonas. 



