. 
1878. ] 53) VF { Lesquereux. 
T HNIOPHYLLUM DEFLEXUM, sp. nov. 
Pl. LIV, fig. 4. 
Stem or branch narrow, leaves closely imbricated, apparently decurrent, 
their base being covered by fragments of broken leaves decurving to and 
expanding in right angle from the stem, surface smooth. 
The part of a branch figured here is entirely covered with broken frag- 
ments of detached leaves and its surface is nowhere exposed. The leaves 
deflexed along the borders in right angle to the stem, seemingly from above 
the decurrent base, all flattened and parallel, their border generally 
contiguous, measure one centimeter in width and thirty-seven centimeters 
in length to the point where the specimen is broken. The coaly epider- 
mis is on the surface very thin and fragmentary, or spread here and there 
like powder by decomposition ; but the leaves taken altogether appear of 
a somewhat thick consistence. I have of this species only one specimen, 
a large piece of shale, of which a fragment only is figured. Seen with a 
very strong glass, the veins of the surface may be approximately counted 
at twenty in one millimeter space ; the cross wrinkles are also of the same 
size. 
From the flat position of the leaves, all paralleland in the same direction, 
they appear as expanded originally upon the surface of the water. The 
narrowness of the stem also compared with the numerous and long leaves 
seem to indicate a floating plant. The cross section of the leaves show 
both surfaces separated by a thin layer of shale or clay, as if the leaves 
had been in their original state, somewhat inflated or tubulose. 
Habitat. Cannelton. Mr. I. F. Mansfield. 
T ®NIOPHYLLUM DECURRENS, sp. nov. — 
Pl. LL, fig. 4. Pl. LU, fig. 1. 
Stem large ; leaves decurring, narrower than in the former species, ob- 
tuse, sublinear or very slightly enlarged from the base upwards, long and 
thick ; surface same as the former, more opaque. 
Both the figures represent the leaves decurring upon the stem by an 
elongated base, but in Pl. LI, the leaves preserve in their length, as far at 
least as it can be seen, the same diameter all along their decurring base, 
while Pl. LII, they are gradually narrowed downward from their point of 
attachment, forming, as appressed upon another or against each other, 
narrow basilar prominent ridges. The leaves also of fig. LI, are slightly 
broader and more distinctly enlarged upwards. As the trunk of this 
specimen is not decorticated, I could not compare the point of attach- 
ment ; and the characters of texture, facies and size of the leaves being the 
same, I consider them a variable form of a same species, perhaps even the 
variation is caused by a difference of compression and maceration of frag- 
ments of a same tree. The leaves average five to seven millimeters in width, 
crowded, forming by their imbricating and decurring long base a thick 
coatin of coaly bark, which, when destroyed, leaves the surface smooth 
