Earring and Myers—The Rotifers of Wisconsin. 
593 
Notommata Pygmaea Harring and Myers, new species 
Plate LYI, figures 5-8 
The body of this species is short, stout, and spindle-shaped; 
its greatest width is about one third of the total length. The in¬ 
tegument is soft and very flexible, but the outline remains fairly 
constant. It is a moderately transparent species. 
The head and neck segments are short and very broad; their 
length is about two thirds of the width, which is nearly three 
fourths of the greatest width of the body. The anterior trans¬ 
verse folds are not strongly marked. The abdomen increases 
slightly in width for one half its length and then tapers gradually 
to the tail, which has a single, inconspicuous, rounded median 
lobe. The foot has two short, broad joints. The toes are short, 
straight, and conical; at mid-length they are abruptly reduced to 
slender, acute points. 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 length of the body; the post-oral portion projects 
as a slight chin. The auricles are short and stout, and the cilia- 
tion is continuous with the corona. 
The mastax is virgate, and all its parts are of very simple form. 
The rami are approximately triangular in ventral view and have 
well developed alulae; at the extreme anterior point they are bent 
at a nearly right angle, and the dorsal portion is obscurely den¬ 
ticulate. The edges of the rami are produced as thin lamellae, 
giving the effect of a semi-domed structure, which effectively sup¬ 
ports the mastax during the pumping action. The fulcrum is a 
long, slender, straight, and slightly tapering rod, without any 
posterior expansion or crutch. The unci have a short, broad basal 
plate and a single, well developed ventral tooth. The manubria 
are somewhat curved rods, slightly expanded at both ends. The 
gastric glands, oesphagus, stomach-intestine, ovary, and bladder 
are normal. The foot glands are large and elongate-pyriform. 
The retrocerebral organ consists of a nearly spherical sac open¬ 
ing on the corona through a long tubular duct, and two subcere¬ 
bral glands partly fused with the very large, pyriform ganglion. 
No bacteroids are present in either sac or glands. The eye-spot 
38—S. A. L. 
