598 Wisconsin Academy of Sciences, Arts, and Letters. 
is a narrow, membranous plate, while the left is very large and 
roughly triangular; near the external angle there is a prominent, 
hooklike posterior projection. Each uncus has three functional 
teeth, slightly clubbed at the tips and united by the basal plate 
for a considerable part of their length. The ventral tooth of the 
left uncus does not reach the manubrium, but is joined to the 
very large second tooth in its entire length. The manubria are 
broadly triangular anteriorly; the median rib is nearly straight. 
In front of the ventral branch of the left ramus there is a slightly 
curved rod, indented at the anterior, lamellar end, and imbedded 
in the ventral wall of the mastax; its function is no doubt to sup¬ 
port the mouth, but it is without any counterpart on the right 
side. 
The oesophagus is long and slender. The gastric glands, sto¬ 
mach-intestine, ovary, and bladder are normal. The foot glands 
are moderately long, slender, and slightly club-shaped. 
The ganglion is large and saccate; the eye-spot is at the 
posterior end. The retrocerebral sac is nearly hemispherical, 
vacuolate, and fairly large; only infrequently does it contain bac- 
teroids. There is no trace of the subcerebral glands. 
Total length 160-200/x; toes 8—10/x; trophi 24/>t. 
Notommata silpha is widely distributed, but usually in small 
numbers. 
This species is readily recognized by the unusual form of the 
corona, the much reduced, wrinkled abdomen, and the shape of 
the toes. Whether Gosse’s Notommata forcipdta belongs here or 
not is uncertain; if it really has auricles, as stated by Gosse, it 
is obviously different, but the rest of his description fits N. silpha 
fairly well, and it is possible that he may have mistaken the frontal 
papillae for auricles. 
notommata pseudocerberus de Beauchamp. 
Plate XLVII, figures 6-9 
'Notommata cerberus de Beauchamp, Arch. Zool. Exp. IV, 6 (1907): 4, 
figs. 1, 2; Zool. Anz. 31 (1907): 905, figs. 1-3; not Notommata cer¬ 
berus Gosse, 1886. 
Notommata pseudocerberus de Beauchamp, Zool. Anz. 33 (1908): 400; 
Arch. Zool. Exp. IV, 10 (1909): 101, 116, 198, 337, figs. VII B, XX, 
PI. 1, figs. 1, 2, PI. 4, fig. 33, PI. 8, figs. 106, 107. 
