Harring (& Myers—Rotifer Fauna of Wisconsin — II, 539 
The dorsal antenna is a small setigerous papilla in the normal 
position; the lateral antennae are on the posterior fourth of the 
body. 
The corona is very slightly oblique and consists of a marginal 
wreath of cilia with lateral, auricle-like tufts of longer cilia for 
propulsion; the apical plate is unciliated and the buccal field 
evenly covered with short, close-set cilia. 
The mastax belongs to a type intermediate between the virgate 
and the forcipate, the piston playing but a very subordinate role 
in its function. The fulcrum is rather short and very broad at 
the base, tapering rapidly to the blunt posterior end. The rami 
are broadly triangular at the base and the posterior portion lyrate; 
the basal apophysis is abnormally large, somewhat curved and 
separated from the rami proper by a deep, rounded sinus. The 
inner margins of the rami are equipped with a unique and com¬ 
plicated dental armature. The teeth are naturally divisible into 
three groups: ventral, oral and posterior. The ventral group 
consists of 12-14 comblike teeth; their length increases gradually 
to a point somewhat beyond mid-length, decreasing from there 
towards the oral group. This consists of four extremely large, 
stout, slightly curved and acutely pointed, interlocking teeth; the 
relative length and development of the individual teeth is some¬ 
what variable, especially in the case of the second and third 
tooth on each side. The posterior group consists of three long, 
slender, acutely pointed, interlocking needle-like teeth in each 
ramus. Each uncus has three long, slender, unequal teeth, clubbed 
at the tips; two rest on the rami at the base of the comb-like teeth 
and one on the posterior end, beyond the oral group of teeth. 
In the right uncus the ventral tooth is largest and the second 
somewhat smaller; in the left uncus the ventral tooth is relatively 
small and the second as large as the right ventral. The basal 
portion of the manubria is broad and plate-like, the posterior 
rod-like and decurved at the end. The piston is relatively small 
and weak. 
The oesophagus is short. The gastric glands are rather small 
and rounded. There is no constriction between the stomach and 
instine. The ovary and bladder are normal. The foot glands are 
small and pyriform. 
The ganglion is large and saccate. The retrocerebral sac is 
fairly large and pyriform; it is usually crowded with bacteroids 
and opaque to transmitted light. The duct can not be traced be- 
