52. Corona with a few long bristles, or else with bunches of bristles alter' 



nating with the cilia of the inner ring 53. 



No bristles on the corona 55. 



53. With two to four long bristles on the corona 



Synchaeta Ehrenberg 

 With bunches of bristles in the inner ring of cilia 54. 



54. No eye, or else body saC'like 



Epiphanes Ehrenberg 

 (7\[otops Hudson) 

 (Hydatina Ehrenberg) 

 With one eye; body tapering; with a hump on one side 

 Cyrtonia Rousselet 



55. Foot projecting from the rear of the ventral side of the body 56. 

 Foot projecting squarely posteriorly 57. 



56. Back almost flat 



Asplanchnopus de Guerne 

 With a decided hump on the back 

 Enteroplea Ehrenberg 

 {Trxphylus Hudson) 



57. No eyes 



Pleurotrocha Ehrenberg 

 With one to three eyes 58. 



58. With one eye 59. 

 With two or three eyes 62. 



59. Eye near the front 



Monomviata Bartsch 

 (Furcularm Ehrenberg) 

 Eye in the neck 60. 



60. Skin with many cross folds permanently fixed 



Taphrocampa Gosse 

 Skin not so, although sometimes jointed 61. 



61. Corona regular 



Proales Gosse 

 With a lobe bearing longer cilia on each side of the corona; these lobes 

 (auricles) are usually contracted and not visible when the animal is 

 not swimming 



'hlotommata Ehrenberg 

 (Includes Co pens Gosse) 



62. With three eyes 



Eosphora Ehrenberg 

 With two eyes 63. 



63. With a dorsal projection from the corona bearing two eyes 



Rhmoglena Ehrenberg 

 {Rhinops Hudson) 

 No dorsal projection from the corona 64. 



