Earring and Myers—The Rotifers of Wisconsin. 639 
The ganglion is rather small and saccate. The retrocerebral 
organ consists of a small, clear sac and two subeerebral glands, 
as large as the sac; their contents is granular, but they do not 
contain bacteroids. The eye-spot is large and very dark red: 
it is at the posterior end of the ganglion. 
Total length 350-450//; toes 24-30//; trophi 65//. 
Eosphora ehrenbergi is not common; when it is found, it gen¬ 
erally occurs in large numbers. 
Eosphora Therina ITarring and Myers, new species 
Plate LIX, figures 1-5 
The body of this species is broad, nearly parallel-sided, and 
very robust ; its greatest width, at mid-length, is a little less than 
one third of the total length. The integument is very flexible, 
but the outline remains fairly constant. The entire body is very 
transparent. 
The head and neck are not separated by any external fold; 
their combined length is somewhat more than one fourth of the 
total length, and the anterior width is a little less than the greatest 
width of the body; a well marked transverse fold is present be¬ 
tween the neck and the abdomen. The abdomen is slightly nar¬ 
rower at the anterior end than at mid-length; from there it tapers 
gradually to the very small tail, which projects very little be¬ 
yond the base of the foot. There is no marked reduction in width 
at the junction of the abdomen and the foot; the latter is ob¬ 
scurely three-jointed and conical, its posterior width being only 
one half of the width at the base. The toes are rather short, 
about one eighteenth of the total length, conical, and slightly com¬ 
pressed laterally; posteriorly they end in a minute, but well 
marked claw-like tip. 
The dorsal antenna is unusually far back on the anterior por¬ 
tion of the body; the lateral antennae are approximately in the 
normal position. They are all small, setigerous pimples. 
The corona is frontal and consists of a marginal wreath of 
cilia, interrupted dorsally and passing in a curve to a lateral, 
auricle-like area of strongly developed cilia; the ventral arcs meet 
immediately below the mouth. The buccal field is faintly ciliate. 
The mastax is of a modified virgate form, in which the pump¬ 
ing action has been almost completely lost and an adaptation 
