VORTICEL'LIDZ, a family of infueoria, remarkable for beauty, and containing a great number of species, to which, from their form, the name of bell or bell-flower animalcules is often given. The genus Torticella consists of minute cup-shaped or bell-shaped crea tures, each placed at the top of a long flexible stalk, the other end of which is attached to some object, as the stem or leaf of an aquatic plant. Around the edge of the bell or cup is a fringe of rather long cilia, the motion of which brings food to the mouth. The stem is flexible, and is sometimes stretched out to its full length, sometimes contracted ire a spiral form. The contraction takes place instantaneously upon any alarm, the cilia at the same time vanishing; and it is very interesting to watch a group of vorticelks, which may often be easily done with a Coddington lens, when they adhere to the inside of the glass of an aquarium. The stem is often beautifully branched, the vortieella becoming a compound animal, like many zoophytes, and the whole contracts or is extended at once. The stem, slender as it is, is a tube, through the whole length of
which runs a minute muscular thread. A cup or hell of a rorticella sometimes develops a new fringe of cilia at its point of junction with the stem, becomes detached from the stem, and begins to move freely through the water, till it finds a new place on which to fix itself, reproduction thus taking place by gemination. Reproduction also takes place by encapsulation. Sec INFUSOBIA. To the family vorticellidte belongs the genus glentor, having a trumpet-shaped body, and therefore receiving the popular name of trumpet animalcules. They swim freely through the water. at the same time rotating on an axis, and attach themselves to objects by a sucker at the lower or narrow end. They have a fringe of cilia round the mouth, and the body of some species is covered with cilia. They are very voracious. They may often be found adhering to a twig or the stem of an aquatic plant, collapsed into minute masses of green jelly.