THE WHEEL ANIMALCULES (ROTATORIA) 609 



97 (3) Mouth nearly in center of large corona. . Order Floscularida . . 98 



Corona circular or drawn out into lobes, points, or arms. Foot never ending in two toes 

 placed side by side. Mostly attached or tube-bearing rotifers, the foot forming a disk for 

 attachment; a few free-swimming species in which the foot ends in a single toe, sometimes 

 accompanied by a dorsal spur. 



98 (101) Free swimming; foot ending in a single toe. 



Family Microdonidae . . 99 



Corona circular, with mouth in center, an outer wreath of active ciUa; ciUa about the mouth 

 larger and bristle-like. One eye. 



99 (100) Foot as long as body Microcodon Ehrenberg. 



Body slender, corona with raised borders, sHghtly bilobed; foot slender, straight, ending in 

 a single toe; no dorsal spur. 



Only one species (Fig. 931) Microcodon clavus Ehrenberg. 



100 (99) Foot not more than half as long as body. . Microcodides Bergendal. 



Body not so slender; foot ending in one toe which is sometimes accompanied by a dorsal 

 spur. 



Representative species (Fig. 932). . Microcodides rohustus Glasscott. 



loi (98) Attached, or bearing tubes if free swimming 102 



102 (105) CiUa around corona Family Floscularhdae . . 103 



Corona large, forming a net for the capture of prey. Cilia about its edge usually forming 

 long threads or bristles which do not beat like those of other rotifers, though they may move 

 rather slowly. Jaws uncinate (Fig. 933, D). 



103 (104) Corona circular, or drawn into lobes, or pointed; its ciUa not ir 

 whorls or regular groups Floscularia Oken 



Many species. 



Representative species (Fig. 933, A and B). 



Floscularia proboscidea Ehrenberg. 

 (Fig. 934 and 861, B, page 561). 



F. campanulata Dobie. 



(Fig. 935) i?. M»jto6ffl Wierzejski. 



(Fig. 936) F. edentata Collins. 



