THE WHEEL ANIMALCULES (ROTATORIA) 617 



129 (126) Dorsal antenna very large, with two projections or hooks at its 



side '. Cephalo siphon Ehrenberg. 



Corona nearly circular with a distinct dorsal gap. Ventral antennae small or absent. 



Representative species (Fig. 956). . Cephalosiphonlimnias Ehrenberg. 



130 (122, 133) Not attached nor forming colonies, save that one adult may 

 be grouped with its young 131 



131 (132) Not forming tubes Pseudoecistes Stenroos. 



In other respects like Cephalosiphon. One or two species. 



Representative species (Fig. 954). . . Pseudoecistes rotifer Stenroos. 



132 (131) Inhabiting a tube Conochiloides Hlava. 



Individuals separate or one grouped with its young. One or two species. 



Representative species (Fig. 953). . . . Conochiloides natans Seligo. 



133 (122, 130) In clusters of many individuals, forming usually a spherical 

 colony appearing to the naked eye as a yellowish ball. . 134 



134 (i37) Clusters attached 135 



J 35 ( J 36) No tubes 7 Megalotrocha Ehrenberg. 



Colonies often several millimeters in diameter, attached to plants. Individuals not imbedded 

 in a gelatinous mass; corona broad, kidney shaped. Body usually with two or four opaque 

 warts. Several species. 



Representative species (Fig. 955). 



Megalotrocha alboflamcans Ehrenberg. 



136 (135) Dwelling in transparent gelatinous tubes. . Lacinularia Schweigger. 



Colony, a mass of some mm. in diameter, often appears to be imbedded in a mass of jelly. 

 Corona heart shaped (Figs. 86 1, A, and 865). Several species. 



Representative species (Fig. 861, A, page 561, and Fig. 865, page 575). 



Lacinularia socialis Ehrenberg. 



X 37 ( J 34) Clusters or colonies free swimming. . . . Conochilus Ehrenberg. 

 Two or three species. 



Representative species (Fig. 952). . Conochilus unicornis Rousselet. 



