THE WHEEL ANIMALCULES (ROTATORIA) 597 



54 (SS) Head shield broad, flat, appearing from above like a halo. 



Stephanops Ehrenberg. 

 Several species. 



Representative species (Fig. 899) . . . Stephanops intermedius Burn. 



55 (S4) Head shield arched, in side view appearing hke a hook S^ 



56 (57) Lorica arched and laterally compressed Colurus Ehrenberg. 



Many spedes. 



Representative species (Fig. 900) Colurus grallator Gosse. 



S7 (56) Lorica flattened, wider than high Metopidia Ehrenberg. 



Representative species (Fig. 901). . . . Metopidia ehrenbergiiVexty. 



S8 (53) No head shield Cochleare Gosse. 



Lorica shaped like a coat, covering only the anterior half or less of the dorsal surface. One 

 or two species. 



Representative species (Fig. 902) Cochleare turbo Gosse. 



S9 (52) Foot and toes usually long; if not, upper surface of lorica with long 

 spines Family Dinocharidae . . 60 



Lorica entire, covering head as well as body. Movements often of a leaping character. 



60 (63) Lorica without spines on dorsal surface 61 



61 (62) Lorica weak, hardly noticeable Scaridium Ehrenberg, 



No sculpturing of any sort; toes very long. Two spedes. 



Representative species (Fig. 903). 



Scaridium longicaudum Ehrenberg, 



62 (61) Lorica rough Dinocharis Ehrenberg 



Two spedes. 



Representative species (Fig. 904). . Dinocharis pocillum Ehrenberg. 



