Hawing and Myers—The Rotifers of Wisconsin. 599 
The body is fusiform and moderately slender, its greatest width 
being somewhat less than one third of the total length. The in¬ 
tegument is leathery and the outline fairly constant. It is a 
moderately transparent animal. 
The width of the head segment is equal to its length and a 
little more than one half the greatest width of the body. A trans¬ 
verse fold separates the head from the neck, but there is no con¬ 
striction between neck and abdomen; the latter increases very 
regularly in width for nearly two thirds of its length and then 
tapers gradually to the tail, which has a small, rounded median 
lobe and two very small lateral lobes. The foot has two joints, 
the terminal but half the length and width of the anterior. The 
toes are moderately long, conical, slender, and very slightly de- 
curved; their length is about one twelfth 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 for about one 
fourth of the entire length; the post-oral portion projects from 
the surface of the body as a slight chin. The rostrum or cuticu- 
lar fold above the mouth is well marked. The auricles are moder¬ 
ately long and stout, and the ciliation is continuous with the 
corona. 
The mastax is virgate, but feebly developed, and the trophi are 
of very simple form, adapted to support the walls of the mastax 
only; it is at the end of a short pharyngeal tube. The fulcrum is 
long, slender, and slightly tapering, without any posterior en¬ 
largement. The rami are symmetrical, very broad, lamellar 
throughout, and bent at an obtuse angle at the extreme anterior 
point; there are no marginal teeth or other irregularities on the 
inner edges. The unci have a membranous basal plate without 
any definite inner border, and a single, very slender tooth; on 
each side there are four or five very minute pre-uncial teeth. 
The manubria are very short and expanded anteriorly into thin 
plates. Nearly level with the lower edges of the rami, two slender, 
curved rods are imbedded in the walls of the mastax; their ven¬ 
tral ends rest on the inner surface of the rami, and the dorsal 
ends meet at a considerable distance below the tips of the rami. 
Two vestigial, non-functional salivary glands occupy the posterior 
portion of the mastax. 
The oesophagus is very long and slender. Gastric glands, 
stomach-intestine, and ovary are normal. The bladder is formed 
