[PENHALLOW] A REPORT ON FOSSIL PLANTS 308 
This plant belongs to the genus Pecopteris, which Brongniart 
established in 1828. To it he assigned a large number of related species 
ranging from the Carboniferous to the Permian, while more recently it 
has come to include species from the Mesozoic and even from the early 
Tertiary. It is therefore found that through a well defined series of 
related specific types, tne genus, which is recognized as a very old one, 
is directly connected with existing types to be found in the Gleicheni- 
aceæ, and particularly in the genus Gleichenia, as already shown by 
Potonié, who nevertheless retains Brongniart’s original name (54, 53). 
The former practice of adopting one neme for fossils and another for 
recent forms when the two are recognized to have generic identity does 
not rest upon a sound basis, nor is it conducive to that nomenclatural 
simplification which is a great desideratum at the present time. It 
rather tends to perpetuate and emphasize the ancient idea of the radical 
difference between extinct and existing types, instead of directing atten- 
tion toward a progressive development of related forms. There is, 
therefore, no real reason why the genus Pecopteris should not be known 
in the future as Gleichenia, to which the various species in reality 
belong, and our future practice will conform to this view, in accordance 
with that already instituted by Heer in 1875 (35: III, p. 44, 
pl. iv, v, vi, vii), who relegates to that genus all isi of the typ2 
represented by the present specimen. 
In endeavouring to institute comparison with other specimens from 
nearly related horizons, it appears that no representative of this 
plant is to be found in the collections of the Peter Redpath Museum, 
where the most recent horizon in which any Pecopteris appears is the 
Upper Cretaceous. A specimen to which no specific name has been 
assigned, was collected by Dr. G. M. Dawson, from the Upper Creta- 
ceous of Baynes Sound, B.C. This may possibly be the same as a 
species which Sir William Dawson recognized (8) in the material col- 
lected by Mr. James Richardson, from Hornby Island, B.C., in 1872, 
and which he regarded as closely approaching P. phillipsi of the English 
Oolite, but to which he gave no name on account of the absence cf 
venation. 
Dawson (5) has shown that Pecopteris browniana, Dunker, occurs 
in the Kootanie Series, and, as originally noted by Newberry (44), it 
also occurs at Great Fails, Montana; but since this species has now 
been definitely transferred to the genus Cyathites, it is excluded from 
further consideration. Of the thirteen species of Pecopteris enumerated 
by Knowlton (37), all except one may be readily excluded from the 
present case by reason of their marked differences in the character of 
the foliage. 
