Anthophy´sa mül´leri (fig. 20) has the monad bodies arranged in little heads at the ends of an irregularly branched brown stalk. After a time they become detached and revolve freely in the water.
Dinobry´ina.—Dinobry´on sertulária ([Pl. XI.] fig. 21) forms a minute Sertularia-like polypidom, consisting of rows of cells, each containing an oval monad with a single anterior filament. The two last species are common in bog-water.
Thecamonad´ina.—In these Infusoria the body is inclosed in a firm and sometimes brittle shell or carapace.
Trachelom´onas volvoc´ina ([Pl. XI.] fig. 22) has a spherical red shell, the body being furnished with a single filament and a minute red eye-spot; while Chætogléna volvoc´ina (fig. 23) has an oblong shell, covered with little spines.
Euglénia.—In this family the form of the body is constantly changing, being at one time spherical, at another fusiform or ovate. It is covered with a contractile skin or firmer external portion, and has one or more flagelliform filaments for locomotion. The species are common in stagnant pools, often colouring the water green or red.
Eugléna vir´idis ([Pl. XI.] fig. 24) has a spindle-shaped body when fully expanded, the ends being pale; and at the front end is a red eye-spot.
Astásia hæmatódes (fig. 25), which is probably a form of the Euglena, is found in stagnant pools, which it renders red. It has no eye-spot.
Enchélia.—These Infusoria are found in stagnant water and in decomposing infusions. The body is covered with cilia variously arranged, but there is no integument nor mouth.
En´chelys nodulósa ([Pl. XI.] fig. 26) has a colourless, oblong, irregularly nodular body, coated with very slender radiating cilia, and often exhibits numerous vacuoles. It is frequently found undergoing transverse division (fig. 26 a), the body becoming gradually constricted until it separates into two parts, which become perfect animals.
Alys´cum sal´tans (fig. 39) has an ovoid-oblong, slightly furrowed body, surrounded with radiating cilia, and has a side bundle of long retractile cilia, by means of which it leaps from place to place in the water.