Many of the Rotifers carry their eggs when ripe extruded from the body in two bunches or clusters, as is the habit also of the little microscopic shrimps known as Cyclops. There is a whole group of Rotifers which fix themselves by the tail, when full grown, to some solid support. Each then forms a protective tube or case around itself, from the mouth of which it puts forth its wheel-apparatus and into which it can retire for protection. Some of the largest and most beautiful of the wheel animalcules belong to this group of fixed or sedentary Rotifers. The crown animalcule (Stephanoceros) is one of these, having what are discs edged with vibrating hairs in the common Rotifer–here drawn out into a circlet of tapering lobes like the points of a coronet (Fig. 37 (_bis_), B). Another is the floscule (Floscularia), in which the wheel-apparatus has the form of five knobs arranged on a pentagonal disc around the mouth (A in same figure). Each knob has a bundle of excessively fine, long, stiff, motionless hairs spreading out from it ready to entangle food particles which may drift into contact with them. I used to find the stems of the fresh-water polyp (Cordylophora) of Victoria Dock a sure source of supply of these fine little creatures. When seen under the microscope as brightly illuminated glassy florets on a black ground (by what is called "dark ground illumination") their strange delicacy and beauty cannot be surpassed. A rare species of floscule (which I have never seen) has extra-long and fine filaments, each of which shows a fine streaming current in its substance, and is, in fact, a naked filament of living protoplasm like one of the ray-like filaments of the sun-animalcules. [Illustration: FIG. 37 (_bis_).–Three tube-building wheel animalcules. _A_, Floscularia campanulata. _B_, Stephanoceros Eichhornii. _C_, Melicerta ringens.]