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BULLET IN OF I HE LABORATORIES 
is closely related to P. inteinnedia but differs in having the reverse 
more finely striated and more numerous lateral branches in a given 
space. P. intermedia has them more oblique and less numerous. 
Formation and locality: — Same as the preceeding. 
PINNATOPORA CURVATA, n. sp. 
(Plate XIV, Fig. 4.) 
Zoariuin pinnate, reverse aspect only observed. Midrib straight, 
about o 4 mm. wide, rounded and finely striated. Pinnae about eight 
on each side in 10 mm., unusually oblique, forming an angle of 45° 
with the midrib ; they are from i to 2 mm. long, curved and about 
half as wide as the midrib. 
So far as observed, this species differs from P. striata, Ulrich,* 
from the Keokuk group of Iowa, in the curved and more oblique 
pinnae. Of the latter also there are eight where that species has seven. 
P. dexiiosa, Ulrich,* from the same horizon in Kentucky has the lat- 
eral branches separated by even longer intervals. There are five or 
six in 10 mm. P. intermedia is a more delicate species and has ten or 
eleven lateral branches in 10 mm. 
Formation and locality: — Same as the preceeding. 
PINNATOPORA SUBANGULATA, n. sp. 
(Plate XIV, Fig. 2.) 
Zoarium pinnate. Midrib nearly straight, between 0.3 mm. and 
0.4 mm. wide, with the reverse side more or less angular and marked 
by from three to five longitudinal striae of which the central one is the 
strongest. Pinnae straight, between i and 2 mm. long, about half as 
wide as the midribs, with usually twelve, sometimes eleven or thirteen 
in 10 mm.; they form an angle of from 65° to 70° with the midrib, 
and on the reverse side are finely striated. On old examples the striae 
on both midribs and pinnae bear rows of minute granules. Zooecia in 
two ranges, about nineteen on each side of the midribs in 5 mm., 
with one opposite each lateral branch and two in the space between. 
Apertures circular, surrounded by a distinct peristome, their diameter 
or less apart. Intermediate spaces very finely granulo-striate. Carina 
moderately developed, rather rounded than sharp, with nodular swell- 
ings at intervals corresponding nearly to the length of a zooecium. 
