No. 2.] FRESH- WATER PROTOZOA, 23 



Leptomonas Kent. 



Solitary, attenuated in front, very flexible, and carry- 

 ing one long flagellum. Usually parasitic. 



Fig. 42, representing an animal found in the water of 

 a watering trough, is with some doubt referred to this 

 genus. 

 Rhynchomonas Klebs. 



Ovate, slightly compressed, the anterior end prolonged 

 into a movable process. Slightly contractile. The single 

 flagellum trailing. Mouth near the anterior end. Con- 

 tractile vacuole anterior; nucleus central. Motions slow. 

 R. nasula Klebs, Fig. 65. 

 Cephalothamnium vStein. 



Body elongated, with an obliquely truncated anterior 

 end that forms an acute projection on one side. One chief 

 flagellum about as long as the body, at whose base is a 

 small secondary flagellum and a mouth. Nucleus and con- 

 tractile vacuole anterior. Forming colonies in groups 

 upon the end of a stalk, either simple or branching twice 

 or three times. 

 C ccBSpitosa (?) S. K., Fig. 46. 

 Anthophysa Bory de Vine, 



Animals as in Cephalothamnium. Forming spherical 

 colonies upon the ends of a much branched stalk, the 

 older portions of which are brownish and the younger por- 

 tions colorless. 

 A. vegetans Stein, Fig. 47. 

 Dinobryon Ehrbg. 



Free swimming colonies, yellow to brown, A beaker- 

 like lorica, with an acute posterior end. The younger 

 individuals are mostly attached with their posterior end 

 inside of the mouth opening of the older individuals. With 

 two chromatophores and an eye-spot. Central nucleus and 

 one or two anterior contractile vacuoles. One primary 

 and one secondary flagellum. 

 D. sertularia Ehrbg., Fig. 44. 

 Uroglena Ehrbg. 



Free swimming, nearly spherical colonies, made of 

 many individuals embedded on the surface of a jelly-like 



