kowlton.] DESCRIPTION OF SPECIES. 21 
Sezanne, was certain that his plant was identical with those from 
|ournemouth( British Eocene), and Lesquerenx was unable to "see any 
[ifference whatever " between the English specimens and his Gymno- 
ramma Haydenii. Dr. Newberry, the only one, so far as I know, who 
ias expressed an opinion, while admitting the probable correctness of 
his identification, still inclines to regard the American specimens as 
arietally distinct. In a recent paper on the Laramie group l he writes : 
Two ferns, Anemia subcretacea Saporta and Lygodium Kaulfusii I leer, 
re considered by Mr. J. Starkie Gardner the same with Lesquereux's 
iymnogramma Haydenii and Lygodium neuropter aides. This is possible 
nd probable, but our plants are more robust than the European and 
lay be considered as distinct varieties if specifically identical." Again : 
So I have what Mr. Gardner would probably regard as fronds of 
inemia subcretacea from Point of Rocks, Hams Fork, Carbonado, and 
'schuckernuts, Washington; but most of these are much more r obus 
iian the European forms, and constitute at least distinct varieties." 
I have not had opportunity to examine the specimens to which Dr. 
Tewberry refers, but the specimens in my possession, while in some 
ases slightly larger than the figures of the European specimens, do 
ot seem to me to be uniformly large enough to warrant this separation 
v r en as varieties. Merely slight differences in the size of plants are 
snally of little diagnostic value, since, as is well known, environment 
lays an important part in their development. The English specimens 
re not of a uniform size, as the authors say (op. cit., p. 47) : "This fern 
| found more especially to the east of Bournemouth Pier, and appears 
) have attained its greatest luxuriance when growing with Aro'ids and 
onifers. It decreases in size and abundance in the beds westward, 
>ward Poole Harbor, and at Branksea small pinme only are met with." 
: is, however, possible that it may eventually be found expedient to 
jparate the American specimens under a varietal name. 
The presence of this species in the Montana formation rests, as 
ointed out above, on the authority of Dr. Newberry, who reports 
aving it from Point of Bocks, Wyoming. 1 have not seen specimens 
om that locality. 
Anemia subcretacea was first described from this country (under the 
ame of Gymnogramma Haydenii) from the continental divide between 
lie Flat Mountain arm ot Yellowstone Lake and what was then 
jgarded as the head waters of the Snake River but what is now known 
> be only a small tributary of Snake River. The age of these beds is 
jgarded as Laramie by the members of the United States Geological 
urvey who havemadeinvestigations in the Yellowstone National Park. 
It has also been found at a number of other localities, viz, at Golden, 
olorado; at Potato Hill Gap, on Grand River, near Hot Sulphur 
prings, Grand County, Colorado; at Hams Fork, Wyoming; and 
\ Carbonado and Tschuckernuts, Washington. 
iBull. Geol. Soc. Am., Vol. I, p. 526 (1890;. 
