eye, [255];
vascular system, [247], [251];
dorsal ciliated organ, [247], [254], [256];
nephridium, [253];
reproduction, [256];
sexually mature, [276], [276] f.;
sexual dimorphism and Heteroneid phase, [276] f.;
epitokous (= epigamous) and atokous phase, [277] n.;
from fresh water, [284];