V. ventrosa, apertura sinuata, cirro utrinque ventrali. Big-bellied vorticella, the aperture sinuated, two tufts of hair on each side of the belly. It is found in ditch water.
298. Vorticella Nasuta.
V. cylindracea, crateris medio mucrone prominente. [Plate XXVII.] Fig. 38, 39. Cylindrical, with a prominent point in the middle of the cup.
An animalculum that is invisible to the naked eye; but the microscope discovers it to be furnished with a rotatory organ, which encompasses the middle of the body.
It is pellucid, cylindrical, of an unequal size; the fore-part, a, truncated and ciliated, and a triangular prominence, e, in the middle of the aperture; the hind-part is obtuse, with a point on each side of the middle of the body. This is the appearance of the little creature when in motion; but when the water is nearly exhaled, some further parts of its structure are rendered visible; two rotatory organs are now observable; one on the fore-part, and the other encompassing the middle of the body, h h; the hairs of the latter are in vehement motion. Other fascicles of moving hair may likewise be observed, and the variegated and quick motion of this apparatus is very surprizing, especially if the animalculum be big with young, moving at the same time within the mother.
299. Vorticella Stellina.
V. orbicularis, disco moleculari, peripheria ciliata. Orbicular vorticella, with a molecular disc, and ciliated margin.
300. Vorticella Discina.
V. orbicularis, margine ciliato, subtus convexo-ansata. [Plate XXVI.] Fig. 8, 9, 10. Orbicular vorticella, the edge ciliated, with a kind of convex handle on the under-side.