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of body, posterior to intestinal bifurcation. Shell gland, compact, oval 
body, smaller than and posterior to ovary. Vitelline glands dorsal 
to intestine, in compact u-shape mass, anterior end closed, arms extend 
from ovary to posterior end of body. Seminal receptacle and Laurer’s 
canal absent. Uterus passes caudad from shell gland, traverses length 
of body in four coiled and straight longitudinal tubes, the last tube pass- 
ing cephalad in median plane between intestinal ceca, ventral to eso- 
phagus and opening in thre genital pore. Uterine tubes not confined to 
intercecal region. Genital pore small, ventral to pharynx. Seminal 
vesicle, large, elongated, sac-like, filled with sperm cells, extends from 
common genital pore caudad to plane slightly posterior to ovary. Cirrus 
absent. Testes absent in mature forms. Testes evidently atrophied and 
degenerated, a case similar to that described by Looss (1902, p. 677) 
in Monostomum reticulare and Monostomum aberrans. (A small, com- 
pact, globular body was found in one immature specimen near the in- 
testinal bifurcation. This body may prove to be a testis.) 
Eggs oval, thin shell, operculum absent, small blunt polar stalk 
present. Size: 0,09 to 0,18 mm. long by 0,06 to 0,13 mm. wide. 
Habitat. Lungs of painted terrapin, Chrysemys marginata, in 
Minnesota lakes and Mississippi River. 
In attempting to determine the systematic position of this mono- 
stome, it appears to be a mis-fit for it fits neither in Looss’ (1902) nor 
in Lühe’s (1909) classification and according to Kossack’s (1911) 
classification, which is based on the most recent and thoro revision of 
the monostomes, it cannot be placed in the family Cyclocoelidae on 
account of the blind endings of the intestinal ceca as well as the pre- 
sence of a definite oral sucker and a polar stalk on the egg. On the 
other hand it cannot find place in the family Notocotylidae on ac- 
count of the absence of ventral glands or ribs and also on account of 
the anterior position and the different relation of the genitals. In ge- 
neral it is more like the Cyclocoelidae than the Notocotylidae but 
either a new family will need to be created or the family Cyclocoe- 
lidae must be expanded so as to include this new monostome. One 
hesitates to create a new family on the basis of a single genus and for 
the present we would suggest that a new genus Aorchis (without testes) 
be established under the family Cyclocoelidae. As a specific name 
we suggest extensus (uterine coils stretched out) as a diagnostic one. 
The detailed description and discussion, together with drawings of 
this new monostome which are now completed, will be published as soon 
as the study, new in progress, of immature specimens is completed. 
July, 23, 1914. The Zoological Laboratory, the University of Nebraska. 
