110 Dr. A. C. Stokes on new Hypotriclious 



region composing about one third the length of the entire 

 body, the frontal lip small ; locomotive styles small and short, 

 the frontal ten in number,' the anterior three largest ; ventral 

 styles five, the posterior two in close proximity to the anal, 

 the three anterior arranged in a single longitudinal series ; anal 

 styles five, usually very flexible and active; marginalsetas 

 scarcely projecting except posteriorly ; right-hand margin of 

 the peristome-field sigmoid ; contractile vesicle spherical, near 

 the centre of the left-hand body-margin ; dorsal hispid set^ 

 small and inconspicuous. Length of body ^^-o inch. 



Hah. Shallow pools, in early spring. Movements active. 



This agile colourless form is notable for its small styles ; 

 they are the most minute that I remember to have observed 

 on any member of the Hypotricha. 



Oxytricha hifaria^ sp. nov. (PL III. fig. 9.) 



Body oval, less than three times as long as broad, the right- 

 hand lateral border convex, the left-hand margin flattened, 

 the anterior extremity bearing a prominent, crescentic, lip-like 

 projection, the posterior extremity obtusely pointed, its left- 

 hand margin obliquely rounded ; ventral styles five, scattered, 

 the posterior one in close proximity to the anal styles, the 

 latter five in number, forming two distinct and completely 

 separated groups, the most posterior of which is composed of 

 two large styles projecting beyond the body-margin, the ante- 

 rior cluster being formed of three smaller elements placed 

 above and to the left-hand side of the posterior group, and 

 not extending beyond the margin of the body ; peristome 

 reaching to the centre of the ventral surface, the right-hand 

 border ciliate and bearing a narrow membrane, a linear series 

 of endoral cilia depending from the central region of the peri- 

 stome-field ; marginal setee uninterrupted, longest and largest 

 on the posterior extremity ; nucleus double, the nodules large, 

 ovate ; dorsal hispid setse short and inconspicuous. Length 

 of body yiu inch. 



Hah. An infusion of hay. Endoplasm granular, brownish 

 and semiopaque. Movements rapid and erratic. 



This Infusorian is quite variable in contour, being often 

 evenly oval or elliptical, wdiile other individuals appear with 

 the frontal region somewhat curved towards the left-hand side. 

 The essential characters, however, are constant, and by them 

 the animalcule can readily be recognized as distinct from 

 previously recorded members of the genus, the peculiar and 

 distinguishing arrangement of the anal styles making it easily 

 separable from other Oxytrichce. 



