1878. ] 315 [Lesquereux, 
On the Cordaites and their related generic divisions, in the Carboniferous 
formation of the United States. 
By L. LESQUEREUX. 
(Read before the American Philosophical Society, March 1, 1878.) 
N@GGERATHI 2. 
This family of plants was established by Brongniart on a species of 
Sternberg, Neggerathia foliosa, described in Flora der Vorwelt, II, p. 28, 
Pl. XX, already in 1852. The species is represented by a slender stem or 
rachis, bearing obovate, alternate pinnules, attached to the rachis by a 
narrowed base, with simple, straight, dichotomous nerves, slightly pro- 
jecting at the borders. This plant whose relation was not recognized by 
Sternberg has not been found since. Gceppert, who received specimens 
from Sternberg, described and figured it again in his Gattungen, and con- 
sidered it as a fern related to Cyclopteris. Brongniart, however, com- 
paring it to species of Zama, he placed it between the Cicadw and the 
Conifers, a place which seems legitimate. The large number of species de- 
scribed since as Neggerathia are all of uncertain affinity, and apparently 
referable to the following generic division, that of the Cordattes ; at least, 
IT admit them into it. The leaves of Nwygerathia are two sided, those of 
the Cordaites are in spiral order ; we have none of the first. 
Brongniart in his Tableau des Genres, 1849, established, under the name 
Pychnophyllum, a second genus of the same family from another of 
Sternberg’s species, Mlabellaria borassifolia; while about at the same time 
Unger described it as Cordaites borassifolius, 1850. Sternberg had referred 
his plant to the Palms, but Corda, who in 1845, admirably defined its 
characters by microscopical analysis of its structure in his Beitriage, p. 44, 
Pl. XXIV and XXYV, separated it from the Palms, and found its affinity to 
Lomatofloios and Sigillarta, comparing it to species of Dracena of our 
time. The preservation of the name of Cordaites, in deference to the ad- 
mirable work of Corda, is indeed legitimate, and has been until now gen- 
erally preserved. 
GROUP OF CORDAITES. 
Perhaps no remains are more generally and abundantly found in the 
coal measures, from the Devonian to the Permian, than those of Cordaites. 
They are generally fragments of ribbon-like long leaves, most rarely found 
in connection with the stems ; for since Sternberg whose specimens were 
used by Corda for his illustration of stems and leaves, I do not know that 
until recently any specimens of Cordaites have been found anywhere with 
leaves connected to a stem, except one figured here which I discovered 
years ago in the upper anthracite Salem vein, near Pottsville, Pennsyl- 
vania. Even single leaves of Cordaites are rarely found entire, or in their 
whole length. In some coal beds of Illinois layers of shale one foot thick, 
or more, are composed, so to say, of those leaves heaped and pressed one 
