ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 661 



part of the dorso-lateral border, that are constantly present but which 

 vary somewhat in size and form. Spirostomum loxodes n. sp. in ex- 

 ternal contour bears a striking resemblance to Loxodes ; it approaches 

 nearest to S. teres C. & L. The lorica of Vaginicola leptosoma n. sp. 

 resembles in form V. attenuata (From.) S.K., but is just twice as 

 large, besides differing in the proportion borne by the length to the 

 width. In Cothurnia annulata n. sp. the enclosed animalcule differs 

 from all hitherto known species in the possession of a transversely 

 striated cuticular surface, and the ridge-like elevation encircling the 

 central portion of the body ; the lorica also differs in form from that of 

 other species. Litonotus vesiculosus n. sp. resembles L. Wrzesniowskii 

 S.K. Its chief diagnostic characters, in the internal structure, are 

 the presence of very many minute, quickly and irregularly pulsating 

 contractile vesicles scattered about the cortex, while in the animalcule 

 most resembling it the pulsating vacuole is large, single, and located 

 near the origin of the caudal extremity. Litonotus carinatus n. sp. 

 cannot easily be mistaken for any other species of the genus. 

 Litonotus trichocystus n. sp. to a certain extent resembles L. fasciola 

 (Ehr.) S.K. It is, however, easily distinguishable by its shorter 

 and less conspicuously flattened neck-like part, and especially by the 

 number and arrangement of the trichocysts, which are constant. 

 Chilodon fluviatilis n. sp. differs from all other forms in its shape, 

 and its preference for water not entirely still. Chilodon caudatus 

 n. sp. has the postero-terminal border of the dorsum continued as an 

 acuminate and rigid spur which, with the prominent anterior lip, 

 renders this infusorian readily recognizable. Dexiotricha n. gen. 

 approaches nearest to the Bursariadse of Stein ; but diverges widely 

 from the members of that family in the absence of the conspicuous, 

 excavate peristome field, and especially in the presence of the row of 

 adoral cilia on the right-hand side instead of the left, and in the 

 presence of a ciliated jjharynx, a feature to be distinguished only 

 under high amplification and the most favourable position of the 

 infusorian and the direction of the illuminating ray. One species, 

 D. plarjia n. sp. is described. 



Dr. A. C. Stokes also describes and figures * the following. 



Atradonema tortuosa n. sp. differs from the hitherto only known 

 species, A. teres Stein, in being less fusiform. The single fla- 

 gellum arises within the pharyngeal passage, a point on the wall, pre- 

 sumably the roof, serving as the basis of attachment. In Noto- 

 solenus, primarily described by the author as Solenotus, although 

 an oral aperture has not been actually discerned, yet the appearance 

 of what seems to be a short pharyngeal tract is so constantly present 

 that an oral orifice probably exists and the animalcules must be re- 

 moved from the neighbourhood of Stein's Colponema and placed near 

 Dijjardin's AniHonema. In N. sinuatus n. sp. the appearance of a 

 pliaryngeal tract is more clearly defined than in the other species, 

 and the infusorian is by far the largest of those hitlierto observed. 

 Faramcecium trichium n. sp. is nearest to P. bursaria (Ehr.) S.K., 



♦ Amer. Natural., xix. (1885) pp. 433-43 (10 %s.). 

 Hf-r. 2.- Vol. V. 2 X 



