CLADOPHLEBIS. 101 
1877. Pecopteris exiliforme, Geyler, Paleontographica, vol. xxiv. p. 226, 
ple xx fies 
1878. Pecopteris polymorpha, Dupont, Bull. Ac. R. Belg. sér. ii. vol. xlvi. 
p. 387. 
1889. Aspidium Dunkeri, Fontaine, Potomac Flora, p. 101, pl. xxii. fig. 9; 
pl. xxv. figs. 11’ and 12; pl. xxvi. figs. 2, 8, 9, 18; pl. liv. 
figs. 3 and 9. 
Pecopteris Browniana (in part), Fontaine, Joc. cit. p. 88, pl. xxiii. 
fig. 6; pl. xxvi. figs. 3 and 13. 
1890. Pecopteris exilis, Yokoyama, Journ. Coll. Sci. Japan, vol. iii. p. 35, 
pl. i. figs. 8-10. 
1890. Pecopteris Geyleriana, Nathorst, Denkschr. k. Ak. Wiss. math.-nat. 
Cl. vol. lvii. p. 48, pl. iv. figs. 2-6. 
Type. Imperfect fragments of pinne. 
Dunker founded the species Pecopteris polymorpha on a few 
fragments of a frond from the North German Wealden; some years 
later Schimper altered the name to P. Dunkeri, because Dunker’s 
specific name had been previously used. The following definition 
of the species by Schimper corresponds closely with the original 
description as given by Dunker :— 
‘‘Fronde bi- vel tripinnata, pinnis patentibus, circa 2-3 cm. 
longis, alternis; pinnulis inferioribus oblongis repando-incisis, 
superioribus oblongis, obtusis, approximatis, terminalibus conflu- 
entibus; nervis indistinctis; rachi primaria sulcata, rachibus 
secundariis tenerrime striatis.”’ ! 
I have adopted the generic name Cladophlebis in the absence of 
any fertile pinnules with characters sufficiently distinct to allow 
of reference to a genus suggestive of natural affinity. 
Frond tripinnate, rachis of medium breadth, pinne approximate, 
alternate and spreading, giving the whole frond a somewhat 
deltoid form, tapering rapidly towards the apex; pinnules small, 
entire and somewhat falcate, attached by the entire base, or longer 
and lobed, and narrower towards the point of attachment ; venation 
indistinct, midrib fairly well marked. 
If Schenk’s figure of Cladophlebis Dunkeri? be examined carefully, 
it will be seen that the tripinnate character gives place to the 
bipinnate form in passing from the lower to the upper end of the 
axis, on the right-hand side of the specimen. The parts towards 
1 Trait. pal. vég. vol. i. 1869, p. 539. 
? Paleontographica, vol. xix. pl. xxvi. fig. 1. 
