1878. } d21 [Lesquereux. 
It farther and gradually increases in width to seventeen millimeters at the 
broken end, eleven centimeters from the base. Other leaves from the 
same locality are exactly linear, seventeen millimeters in diameter, while 
others still, fifteen millimeters above the point of attachment, gradually 
diminish in width upwards to fifteen millimeters I remark their dimen- 
sions to show the variety of size of leaves of this genus, not merely in com- 
parison with each other but in different parts of their length. 
I refer to this species leaves found in large numbers at the same locality 
as the specimen figured, some of which are flat and linear, others with 
borders curved inside or half cylindrical, others still true cylinders, not 
larger than a goose-quill, seemingly coming out of a pedicel or stem, as 
they are often found in bundles and enlarging upwards in proportion as 
the borders become more and more open and flattened. The nervation is 
of the same type, the epidermis thick ; they represent in their cross sec- 
tions an oval line, like figure 3 of Grand’ Eury, Pl. XVIII. 
Habitat. Upper coal measures of Pennsylvania, Lower coal measures 
of Missouri; middle and lower coal of Illinois, where it abounds, at Col- 
chester especially, St. John and Du Quoin. 
CORDAITES MANSFIELDI, sp. nov. 
Pl. XLIX, fig. 1, 1b, 2. Pl. XLVIL fig. 4, 40. 
Stem covered with a thin bark of polished coal, marked by numerous 
sears of the convex base of leaves, either imbrivated or more or less distant, 
disposed in spiral. Leaves long, erect, nearly exactly, linear, gradually 
diminishing toward the top to an obtuse point, averaging fifteen millime- 
ters in diameter, distinctly and distantly nerved ; primary nerves fifteen to 
eighteen in one centimeter, with two to four intermediate veins ; surface 
rugose across as in the former species ; branches oblique with imbricated 
leaves of proportionate size. Flowers composed of four sepaloid involu- 
cres, borne upon simple flexuous pedicels, to which they are attached by 
short peduneles. 
As seen from the splendid specimen figured here and from a number of 
others quite as remarkably well preserved, the species is characterized by 
its long, erect, linear leaves, whose surface is marked by a strong nerva- 
tion (12 enlarged double, 1” enlarged four times) rounded and narrowed to 
the point of attachment, reduced to half the diameter of the leaves, per- 
fectly entire and obtusely pointed. The stems are covered with a thin 
coating of coaly, shining bark, where the scars are distinctly marked, but 
no more so than upon the subcortical surface. The branches apparently 
form the axils of the leaves, one of which is seen, fig. 2, bears leaves pro- 
portionate to their length and their age, imbricated, linear-lanceolate, ob- 
tusely pointed, with a nervation of the same character, reduced, of course, 
to proportionate dimensions by the size of the leaves. Another specimen 
bears a branch two to three centimeters thick, diverging in the same 
degree as that of the figure, twelve centimeters long, with leaves propor- 
tionate in size, the largest already fifteen centimeters long, all imbricated, 
PROC. AMER. PHILOS. soc. xvil. 101. 2N. PRINTED MARCH 27, 1878. 
