OxytnchiHa7\ infusorial animalcules. 593 



in O. cicada, and perhaps O. pullaster. The Trichoda nasamomum, 

 and T. oethiopica (Ehr.) belong, in Dujardin's opinion, to Oxytricha, 

 so also the Urosfyla, whilst Oxytricha cicada (Ehr.), becomes a 

 species of Ploesconiens. 



Oxytricha rubra {Trichoda piscis et patens, M.) — Body of a 

 brick-red colour, linear in shape, plane on the under side, and equally 

 rounded at the ends ; posterior end provided with setee. Found 

 in sea water. Size l-140th. 



O. pelionella {Trichoda pelionella, M.) — Body white, smooth, 

 slightly depressed, equally rounded at both ends, often broader in 

 the middle ; head not separate ; mouth ciliated ; tail provided with 

 setae. Each animalcule has two oval male glands, and between them 

 a single round sexual vesicle. When self-division commences four 

 glands are developed, and then the vesicle divides. Ehrenberg 

 counted ten cilia anteriorly, and four or five setae posteriorly ; the 

 anal outlet is at the base of the setse. Found in infusions. Size 

 l-720th to l-280th. 



O. caudata. — Smooth, white, linear-lanceolate in shape, rounded 

 anteriorly, attenuated posteriorly in the form of a tail, which is 

 provided with setae. Found in fresh water and sea water. Size 

 l-576th to 1-1 20th. 



0. platy stoma. — Body white, ovato-oblong, under side flat, with 

 marginal setae ; mouth large and ciliated. It swims with a revolving 

 and vascillating motion, and often upon the back. It creeps upon 

 water plants. Found in standing bog water. Size l-240th. 



0. gibba {Trichoda yibba et foeta, M.) — Body white, lanceolate, 

 ends obtuse, middle enlarged, under side flat and furnished with 

 two series of setae, and a large round mouth. This species resembles 

 O. pelionella, but is distinguished by the setae, the two or three 

 contractile vesicles, and sexual glands. This creature is active, and 

 runs nimbly along aquatic plants in fresh and brackish water. 

 Fig. 336 is an under view, fig. 337 a side view. Size l-240th. 



0. pullaster {Trichoda pullaster, Kerona pullaster, M.) — Body 

 whitish, lanceolate, ends obtuse ; ventral surface naked at the 

 middle ; the head, indicated by a constriction, is hairy, like the 

 tail. The mouth is a narrow fossa. Found in water vessels and 

 infusions. Size 1 -430th. 



