Earring & Myers—Rotifer Fauna of Wisconsin — II. 449 
three fourths of its length and is rounded posteriorly; it is faintly 
plicate longitudinally. The tail is prominent and has a single, 
median, rounded lobe. The foot has two very short joints, the 
terminal smaller than the basal joint. The toes are long and very 
slender; the basal portion, about one third of the total length, is 
straight, and from this point they curve somewhat abruptly out¬ 
wards and downwards, ending in very acute points. Their length 
is about one sixth of the total length. 
The dorsal and lateral antennae are small setigerous papillae in 
the normal positions. 
The corona extends down on the ventral side somewhat more 
than one fourth of the length of the body; the post-oral portion 
projects from the body as a small chin. The auricles are moder¬ 
ately large, and the ciliation is continuous with the corona. 
The mastax is virgate and the trophi very nearly symmetrical. 
The rami are broadly triangular in ventral view and curve gradu¬ 
ally from the base to the dorsal points. The basal apophysis is 
very prominent and is separated from the main portion of the 
ramus by a deep sinus. The inner margins of the rami are armed 
with about twelve minute teeth, beginning a short distance behind 
the basal sinus and continuing to the point of attachment of the 
unci, gradually increasing in length. The fulcrum is long and 
slender, tapering gradually to the posterior end, which is slightly 
incurved. The unci have a single, well developed ventral tooth 
and a rudimentary second tooth, crossing the basal plate diagonally 
to its dorsal angle. Seven small accessory teeth are attached to 
the point of the left uncus and six to the right uncus. The 
manubria are long and slender, with a small basal plate. A pair 
of slightly curved, slender rods are imbedded in the walls of the 
mastax below the posterior edge of the rami and assist in its sup¬ 
port during the pumping action. The epipharynx consists of two 
very slender, tapering and decurved rods immediately in front 
of the unci. 
The oesophagus is moderately long and slender. The gastric 
glands, ovary and bladder are normal. There is no distinct sep¬ 
aration between stomach and intestine. The foot glands are small 
and pyriform. 
The retrocerebral sac is large and rounded; bacteroids are not 
abundant. The subcerebral glands are very large, vacuolate and 
ductless; they are fused to the posterior end of the large, saccate 
