1890.] ' ' [Stokes. 



obliquely truncate ; the lateral margins thinned and projecting beyond 

 the borders of the enclosed animalcule in a wing-like manner, the borders 

 somewhat curved in opposite directions as seen when the Infusorian is 

 examined "end on," or with the anterior or posterior region presenting 

 upward ; posterior border narrowed, obtusely rounded ; the dorsal and 

 ventral aspects apparently encircled by a shallow transverse groove or 

 depression, at times two ; anterior orifice circular, its walls comparatively 

 thick, the two vibratile flagella passing out close to the lateral margins ; 

 enclosed body elongate ovate, granular. Length of lorica T oVcr 

 inch ; greatest width r ^ inch. Hab.— Pond water in early spring. 



Farcilla, gen. no v. — Animalcules persistent in shape, free swimming, 

 the anterior border rounded or minutely and centrally pointed, the pos- 

 terior extremity bifid, the bifurcation remote or approximate ; flagella two, 

 subequal, arising close together from the anterior apex. 



The position of this newly instituted genus in a scheme of classification 

 would probably be in the Heteromonadidne of Biitschli, Goniomona? of 

 Stein and the Amphimonas of Dujardin, having its affinities closer to those 

 of the former than of the latter. Although the single known species of 

 the genius was exceedingly abundant in the infusion, I have not seen the 

 oral aperture in any, neither have I seen anj r in the act of taking food, nor 

 observed any whose endoplasm contained colored granules or other pre- 

 sumable food particles. I therefore assume, on these negative grounds 

 alone, that the genus should be classed among the Flagellata-Pantosto- 

 mata of Saville Kent. 



Farcilla lobosa, sp. nov. Figs. 18-21. — Body more or less ovate, less 

 than twice as long as broad, or in dorsal and ventral view somewhat 

 horse-shoe-shaped, the posterior region bifid, the bifurcation forming 

 about one-half the entire length of the body, straight, somewhat diver- 

 gent or slightly and inwardly curved, tapering and their extremities 

 obtusely rounded ; anterior border convex, with a slight central acumina- 

 tum from which arises the two subequal, vibratile flagella; the lateral borders 

 bearing two rounded lobules or conspicuous protuberances, one on each 

 side, oppositely placed and alternating with the elongated furcated region, 

 the body in transverse optic section presenting an unequally quadrilobate 

 outline, but in lateral view more or less ovate with two opposite, lateral, 

 obtusely rounded wing-like projections or protuberances ; flagella exceed- 

 ing the body in length ; contractile vesicle double, near the centre of the 

 frontal border; nucleus single, located anteriorly near one lateral margin ; 

 endoplasm granular. Length ^ ff to T ^Vg- inch. Hab. A vegetable 

 infusion of decaying Algse and aquatic plants. Movements rotatory and 

 tremulous. 



The body, as far as the prolongation and two lateral protuberances are 

 concerned, is somewhat variable. The latter are, at times, so obscurely 

 developed and are apparently so nearly merged into the anterior body- 

 half that the region becomes subglobose. The posterior prolongations 

 vary in curvature, in their distance apart, and somewhat in their extremi- 

 ties, being at times rounded, at others subacute. The varying direction of 



