470 
PALAEONTOLOGY OF ILLINOIS. 
larger and more distant from each other. The form of the 
pinna and of its division is also totally different in our species. 
Mazon creek; S. S. Strong. 
A number of specimens, representing fruiting pinnae of Pecopteris or Ale- 
thopteris, have been recently obtained from Mazon creek, but are left unde¬ 
scribed, the essential characters, form and position of the son, nervation, etc., 
being too obscure for a satisfactory diagnosis. 
Hymenophyllites furcatus, Brgt. 
Veg. Foss., p. 179, PI. 49, fig. 4 and 5. 
A few small specimens of this species have been collected by Mr. S. S. Strong, 
from the roof shales of Morris. It is rather a sub-conglomerate species, being 
found most abundant at the base of the mill-stone grit, or the top of the red 
sandstone, in the anthracite basin of Pennsylvania. 
Stigmarioides ? rugosus, Sp. nov. 
As much as can be seen from two specimens obtained in con¬ 
cretions at Mazon creek, by Mr. S. S. Strong, the stem is cy¬ 
lindrical, two to three inches in diameter, marked with circu¬ 
lar depressions, points of insertion of branches, or rootlets di¬ 
verging from it all around, enlarged at base, cylindrical, flat¬ 
tened by compression, tapering or diminishing in size from the 
base, half an inch broad to the top, one-fourth of an inch in 
diameter, where these rootlets are broken, two and a half 
inches from the points of insertion. Their surface is wrinkled 
and narrowly striate in their length, and marked by small 
round holes, which appear as the basilar points of attachment 
of branches of rootlets. The cross section of half a cylindri¬ 
cal stem is obscurely seen, and appears to be marked by broad 
tubercles like those of a stem of a Calamites, only much lar¬ 
ger. There is nothing published as yet, which can compare 
with these fossil remains, but the roots of Equisetum Mougeotii, 
Schp., Pal. Veg., pi. 13, fig. 9. I consider them as represent¬ 
ing the rhizomas of some Equisetacece. 
