SELLARDS.| Fossil Plants, Upper Paleozoic, Kansas. 401 
of the frond very thin and shining. Nervation distinct. Mid- 
rib of the pinnules rather prominent, flexuous, decurrent at the 
base, marked by a thin line above, and by a thicker ridge be- 
low. Lateral veins distinct, distant, appearing as a ridge on 
both the upper and under side of the thin lamina. 
This species is referred to the genus Oligocarpia, because of 
the close similarity of the sterile fronds in both the arrange- 
ment and the venation of the pinnules to the fronds of other 
species of that genus. The puncte of the rachis, which become 
on the larger rachises thorn-like projections 14 mm. long and 
obtuse on top, separate the species from other species of 
Oligocarpia. These punctze are placed irregularly on the 
rachis, varying from 14 to 3 or 4mm. apart. From Oligocarpia 
missouriensis D. W. (Flora of the Lower Coal Measures of 
MOSCOW, TO. WO, jolle AO, wha 1, AB jolls AAlL, wes 1LhS Paw By, 24) ihe 
differs further in that the veins are forked at a wider angle, 
and are perhaps more flexuous and curve more in passing to 
the border. From Oligocarpia alabamensis Lx. (Coal Flora, 
p. 266, pl. 47, figs. 1, 1b) it also differs by the strongly decur- 
rent midrib of the pinnule, the tertiary and ultimate pinnee 
having a much more distinct terminal pinnule. Along with the 
normal forms of the species occur several fragments having 
pinne small, lobate, and much narrower than those of the 
typical specimens. The fragments appear to represent a 
slightly different form of the species, or possibly a variety. 
Oligocarpia kansasensis has, in the appearance of the small 
pinnee and the spiny rachis, some resemblance to Sphenopteris 
mixta Schimp., but Schimper’s species is throughout more deli- 
cate, the rachises more slender, the lobes of the small pinne 
(as seen on specimens of the species from Clinton, Mo., and 
mentioned in David White’s treatment of the species) are sep- 
arated by a narrow decurring sinus, while in O. kansasensis 
they are separated by an obtuse, non-decurring sinus. The 
pinnules of Sphenopteris mixta do not reach the size of those of 
O. kansasensis before becoming lobate; while the lamina of the 
Kansas species is clearer, and the venation more distinct. The 
veins fork at a wide angle and traverse the thin lamina in a 
flexuous path. The venation of the ovate pinnules of the 
smaller pinnee is shown in figures 16-18, plate XLV. The sori 
are placed along the pinnule rather nearer the border than the 
midrib. The sori are large and appear to be situated on the 
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