446 Wisconsin Academy of Sciences, Arts, and Letters. 
The oesophagus is long and slender. The gastric glands are 
small and rounded. There is no constriction between the stomach 
and intestine. The ovary and bladder are normal. The foot glands 
are short and pyriform. 
The retrocerebral sac is elongate conical and truncate poste¬ 
riorly ; including the duct its length is fully one third of the length 
of the entire body. The subcerebral glands are elongate and 
fusiform; their length is one half the length of the sac. Bacteroids 
are abundant in the posterior end of the sac and in the glands be¬ 
yond the level of the eyespot. The ganglion is relatively small 
and saccate; the eyespot is at its posterior end. 
Total length 300-350/;t; toes 18-21/x; trophi 38/x long, 45ja wide. 
Notommata codonella is locally fairly common, but seems to be 
found only in neutral or slightly acid waters. We have collected 
it in a shallow bay of Range Line Lake' near Three Lakes, Oneida 
County, Wisconsin, and in ponds in Atlantic County, New Jersey. 
It is closely related to N. cerherns, N. galena, N. collaris, etc.; but 
is readily recognized by the retrocerebral sac and the broad, trun¬ 
cate tail. 
NOTOMMATA THOPICA Harring and Myers, new species. 
Plate XXII, figures 5-9. 
The body is elongate, slender and spindle-shaped; its greatest 
width is less than one fourth of the total length. The integument 
is very flexible, but the outline remains fairly constant. The body 
is transparent, but somewhat milky. 
The transverse folds limiting the head and neck segments are 
well marked. The head segment is short and broad; the neck 
.segment is almost parallel-sided and its width nearly equal to its 
length. The abdomen is deeply striate longitudinally and in¬ 
creases very slightly in width for about two thirds of its length; 
it is rounded posteriorly and ends in a short tail with a very broad, 
rounded median lobe and two minute lateral lobes. The foot has 
two very short joints; the basal joint projects by about one half 
of its length beyond the tail. The two toes are short, slender and 
conical, ending in fairly acute points; their length is about one 
sixteenth of the total length. 
The corona extends down on the ventral side about one fourth 
of the length of the body; the post-oral portion projects from the 
