
New and Little Known American Paleozoic Ostracoda. 189 
especially fig. ro. The duplication of the marginal rim shown in 
his figs. 12 and 13 is not noticed in the Falls specimens, and the 
bent ridge is somewhat thicker in the latter. The last difference is 
explained by the fact that the Pennsylvania specimens occur as 
‘‘casts in buff-colored, non-calcareous shales from the Marcellus 
limestone,” while the Fallg specimens are perfect valves. 
BOLLIA OBESA, N. Sp. 
Patt: MI Vg PIES. 5 a, 0; G. 
Size of valve: Length, 1.52 mm.; height, o.98 mm.; thickness, 
0.5 mm. 
Carapace sub-pentagonal, ends nearly equal, strongly curved, 
back straight, short, dorsal angles obtuse, ventral edge produced 
in the middle. Marginal portion of valves thick, causing them to 
appear unusually ventricose. Horse-shoe ridge unsymmetrical, 
with bulbous extremities, the anterior knob oval, and reaching the 
dorsal edge, the posterior one larger, more nearly round, and ter- 
minating a short distance within the dorsal margin. 
This species is not likely to be mistaken for any other known to 
me. Though clearly a true Jolla, it is very different in its general 
appearance from the associated B. ungula, Jones. 
Position and locality: Devonian Bryozoa bed, Falls of the 
Ohio. 
BEYRICHIA TRICOLLINA, N. Sp. 
Plate XII, Fig. 6. 
Size of left valve: Length, 1.85 mm.; height with frill, 1.25 
mm.; height without frill, 1.0 mm. 
Valves sub-oblong, semi-ovate, moderately convex, with a long 
straight hinge line, and a very wide marginal frill. Without the 
frill the shape of the valves might be called nearly semi-circular, 
were it not for a slight prominence in the postero-ventral portion of 
the curve. Surface exhibiting three rounded tubercles, one near 
the postero-cardinal angle, another, perhaps twice as large, near 
the center of the dorsal margin, the third, smaller than either, 
situated between and a little beneath them. Besides these two, 
slight swellings of the surface may be noticed in the postero-ven- 
