Earring and Myers—The Rotifers of Wisconsin. 621 
riorly. The foot has two short, broad joints. The toes are short, 
conical, and slightly decurved; their length is one eighteenth of 
the total length. 
The dorsal and lateral antennae are small setigerous papillae 
in the normal positions. 
The corona extends down the ventral side about one sixth the 
length of the body; the post-oral portion forms an indistinct chin. 
The auricles are unusual; at the end of a slender peduncle there 
is a tuft of long, closely set cilia, all of the same length, so that 
when the auricles are everted they present a striking illusion of 
a revolving sphere. 
The mastax is of the highly specialized virgate type common 
to the entire genus. The rami are of a lyrate form which bears 
a considerable resemblance to the forcipate type; the anterior 
points are, however, bent somewhat abruptly at an obtuse angle 
toward the dorsal side, and at this point are reinforced by a dia¬ 
gonal, lamellar brace. The alulae are well developed. The ful¬ 
crum is a flat plate, slightly curved in the median plane. The 
unci have two functional teeth; the ventral tooth is long and 
slightly clubbed at the point, while the dorsal is short and has 
a separate tip, which seems to be very loosely joined to it. At 
the tip of the main tooth there is a striated lamella, which evi¬ 
dently corresponds to the pre-uncial teeth present in the mastax 
of a number of Notommatid rotifers. The anterior branch of the 
manubrium is very large and broadly crescent-shaped, its posterior 
tip curving toward the end of the principal, or median, branch, 
which is nearly straight, with a slight ventral curvature at the 
extreme end. The dorsal branch of the manubrium is long and 
curves toward the median plane; expanded posteriorly by a tri¬ 
angular lamella, it contributes the dorsal section of the approxi¬ 
mately hemispherical or dome-shaped arrangement of the trophi. 
The epipharynx consists of two ribbon-like pieces, meeting be¬ 
low the mouth and gradually twisted through an angle of nearly 
180 degrees, at the same time curving dorsally and posteriorly. 
The oesophagus is short; stomach and intestine are not separated 
by any constriction. The gastric glands are very small and nearly 
spherical. The bladder is formed by an expansion of the cloaca, 
as in Notommata pseudocerberus. The ovary is of the normal 
elongate-ovate form. The foot glands are rather small and slightly 
club-shaped. 
