Harring & Myers—Rotifer Fauna of Wisconsin — II. 451 
a narrow, elongate, ventral opening; the alulae are very large 
and curved. The unci are small, triangular lamellae with a very 
faint median tooth. The manubria show no indication of cellular 
division; the basal plate is triangular and the posterior portion 
rodlike, ending in a small crutch. Instead of being approximately 
parallel to the longitudinal axis of the mastax, as in other species 
of the genus, the manubria are nearly at right angles to it. The 
epipharynx consists of two small, very thin, triangular plates, im¬ 
bedded in the walls of the mastax at the sides of the mouth. The 
piston is large, but very weak. 
The oesophagus is moderately long and slender. There is no 
constriction between stomach and intestine. The gastric glands are 
small and rounded. The ovary and bladder are normal. The foot 
glands are pyriform and nearly as long as the foot. 
The ganglion is an elongate, pyriform sac; at its posterior end 
is a rounded, moderately large, ductless retrocerebral sac, which 
does not contain bacteroids. No eyespot is present. 
Total length 175-200/x; toes 25-28/x; trophi 15/x. 
Notommata tithasa is not common; we have found it at Three 
Lakes, Oneida County, Wisconsin, and in ponds around Atlantic 
City, New Jersey; a few specimens occurred in some collections 
made by Dr. H. S. Jennings in the Huron Kiver at Ann Arbor, 
Michigan. This species is readily recognized by the unusually 
long and robust toes. 
Genus TAPHROCAMPA Gosse. 
Notommatid rotifers with cylindric or spindle-shaped, illoricate 
or semiloricate body, marked with permanent or evanescent trans¬ 
verse folds; the foot is rudimentary and the cloaca opens dorsally 
at the base of the toes, under a projecting fold of the integument 
or tail. 
The corona is an elongate oval area covering the oblique anterior 
surface of the head and continuing beyond the mouth on the ven¬ 
tral surface; the marginal cilia are relatively short, except on the 
auricles, which have long and powerful cilia adapted to swimming. 
The apical plate is enclosed by the marginal ciliation; a rostrum 
may be present; the buccal field is covered with short, dense cilia; 
the mouth is approximately in the center of the corona. 
The mastax is virgate with strongly asymmetric trophi; the 
fulcrum is long and slender and nearly at a right angle to the 
