Marshall—American Water Mites of the Genus Neumania. 207 
terior groups are short. The genital plates of the female are 
likewise small, rounded, with the acetabula crowded, small, and 
not very distinct. The genital cleft is long. The entire genital 
area is removed from the posterior end of the body. The legs 
are deep blue, stout and well provided with bristles. The fourth 
and fifth joints of the fourth legs have long coarse hairs and a 
row of stout feathered bristles; a few of the latter are to be 
found also on the third joint. 
The male is unknown. Three females were found in Wiscon¬ 
sin lakes: in Lake Wingra, at Madison, and in Lake Spooner, 
near Spooner. 
Neumania semicircularis nov. spec. 
Plate II, figures 2, 3. 
This is the largest mite in the present collection, the female 
having a length of 1.4 mm. The body is light in color, oblong, 
narrowed dorso-ventrally at the anterior end. The epimeral re¬ 
gion is not extensive, and the spaces between the plates are large. 
The genital area is removed from the epimera and the posterior 
end of the body; in the female the plates are broadly semicircu¬ 
lar in outline, and the acetabula are small. Feathered bristles 
are conspicuous on the third and fourth legs. 
The male is unknown. Six females were found in Wisconsin 
material: from Lake Spooner, near Spooner, and from Mirror 
Lake, near Delton, by the author; and from the Madison lakes 
and the Yahara River, by Dr. R. A. Muttkowski. 
Neumania tenuipalpis nov. spec. 
Plate II, figures 4-6. 
The body is ovate, rather elongated. The epimeral region is 
small, the spaces between the anterior and posterior groups 
large. The braces from the first group of plates are close to¬ 
gether. The genital plates of the male are not extensive. The 
heavy bristles and their sockets are not as conspicuous as in 
some forms. The fourth and fifth joints of the fourth legs have 
each a cluster of long hairs and a row of short, stout bristles; 
both legs have a few feathered bristles. The palpi are unusually 
small, and the second joint is short. The male measures 1.00 mm; 
the female is unknown. 
