400 
PALAEONTOLOGY OF ILLINOIS. 
and the position of the son', our species could also be compared to Asjndium 
Wriglitii, Mitt, of Cuba. Its place is, therefore with the Poli/poclites or Aspi- 
dites of Groppert. 
The specimen fig. 7, is in a concretion form Mazon creek ; the others on shale 
from Morris. 
Found by Mr. S. S. Strong. 
Pecopteris sqamosa, Sp. nov. 
PI. xii, fig. 1 to 4; PI. xiii, fig. 10 and 11, fructif. 
Frond evidently bi or tripinnately divided, triangular or 
lanceolate in outline, with a thick rachis, half an inch or more 
at its base, covered to the top of its last divisions with long, 
linear lanceolate pointed scales, either straight and appressed 
to the stem, or open and diverging all around, even sometimes 
appearing as dried up and crumpled as in fig. 2. The rachis 
of the last divisions is proportionally broad as seen in fig. 1 
and fig. 4, enlarged, and is also either scaly or marked with 
crowded points indicating the base of the scales. Secondary 
pinnae long, linear, slightly tapering to an obtuse point, flex- 
uous or curved upwards, bearing alternate, unequal, narrow 
linear, obtuse, oblong leaflets, nearly perpendicular to the ra¬ 
chis, reflexed on the borders, very close to each other, or often 
contiguous for their whole length, marked with a deep medial 
nerve, but no trace of veins. These leaflets, generally more 
or less irregular in their length, have their fructification indi¬ 
cated by small round dots, placed in two rows, close to the 
borders; the dots are numerous and distinct; their relation 
to the veins and veinlets is unknown. 
The species is quite distinct and only distantly related to Pecopteris platy- 
racliis Brgt. The specimen represented, pi. xii, fig. 4, shows a part of a frond 
of this species, in its process of development. The divisions appear still un¬ 
opened and the outline only of the secondary pinnae with mere traits of medial 
nerves, are indicated by flakes of matter. 
This specimen is upon shale from the roof of the coal at Colchester; the 
other specimens figured are in concretions from Mazon creek. 
