On the Occurrence of Sphenopteris communis in Britain, 87 
VII. On the Occurrence of Sphenopteris communis, Lesqa., 1 
Britain. By R. Kinston, F.R.S.E., F.G.S. [Plate 1] 
(Read 20th March 1895.) 
For some years I have had in my possession specimens of 
a sphenopteroid fern from the Yorkshire Coal Field, which, 
from its fragmentary condition, I was unable to satisfactorily 
determine; but about two years ago I received from Dr Hind, 
Stoke-upon-Trent, more perfect specimens of the same species, 
from the Potteries Coal Field, Staffordshire, from which I was 
enabled to identify my fern as the Sphenopteris communis, 
Lesqx. 
There is often considerable difficulty in identifying 
Carboniferous ferns, and I think this is specially felt in 
connection with the sphenopteroid members of that class 
when dealing with figures and descriptions unassisted by 
authentic specimens; and it was only through the study of 
examples of Sphenopteris communis, Lesqx., from Washington 
County, Arkansas, kindly sent me by Mr R. D. Lacoe, 
Pittston (to whom I have to express my indebtedness in this, 
as on many other occasions, for similar help), that I recognised 
that the Staffordshire and Yorkshire specimens belonged to 
that species. 
Before describing the fern, it is desirable to make a few 
remarks on the horizon from which the American specimens 
were derived. 
In the “ Coal Flora of Pennsylvania,” by the late Mr Leo 
Lesquereux, vol. ii., p. 667, 1880, he gives, in chapter v., a 
“Geographical Distribution of the Plants of the United States 
Coal-Measures.” This chapter is preceded by a “Table of 
Vertical Distribution,’ and in the introductory remarks to 
the table he gives a synopsis of the various horizons." 
It is not my intention to analyse this table, but only to 
refer to some of the divisions which refer to the geological 
position of the American specimens of the plant under 
discussion. 
1 Loc. cit., p..636. 
