406 
PALAEONTOLOGY OF ILLINOIS. 
around it than along its borders; the rachis of the branches 
is also thick, smooth, and on both sides of it are attached the 
groups of sori, three to five in number, in a kind of pyramidal 
position, with a thick short pedicel in the middle. The sori, 
when unopened, are round, marked on the flattened surface by 
four or five lines diverging from the center to the circumfer¬ 
ence. Fig. 2 a. When opened the sporanges appear placed 
like the rays of a star around a central point. These spo¬ 
ranges, oval, elongated or gradually enlarged outwards from 
the narrow point of attachment, deeply concave, finely striate 
within, are all turned to the same side, viz: the point down¬ 
wards and the branches tending obliquely upwards ; in that 
way the upper sori of the pinnse have the point towards the 
rachis, while in the lower ones it is turned from it: see fig. 2, 
enlarged twice, and fig. 2 b, enlarged four times. The spo¬ 
ranges are deeply marked or excavated in the stone, which is 
still more deeply penetrated by the point, and this point appears, 
as said above, to have been attached to a common pedicel by 
filaments now destroyed. 
Found in a concretion from Mazon creek; discovered by Mr. M. S. Hall. 
Staphylopteris asteroides, Sp. nov. 
PI. xiv, fig. 6 to Kt, • 
Frond tripinnate, with straight alternate branches; primary 
pinnae lanceolate pointed or tapering to a point from an en¬ 
larged base; secondary divisions alternate linear, merely formed 
of narrow, filiform, obliquely straight branches or common 
pedicels, bearing groups of sporanges pinnately attached to 
them in pairs and opposite ; sori round at first and before 
maturity, opening at maturity in five lanceolate-pointed lacin- 
ire around a central round point, and forming a star (fig. 7 and 
7 b enlarged). 
This fruiting species is still more remarkable than the former. Groups of 
sori resembling round dots, fig. 8, are seen on the same piece of shale, but on 
