ON GENERA AND SPECIES, 75 
described for the first time. To avoid this I have as far as 
possible followed the plan adopted in my “ Arrangement 
of Ferns,” in 1841, where I have said that “ The authority 
for the specific names being in a parenthesis denotes that 
such species stood formerly under one or other of the 
genera given as synonyms.” 
T have to add that on account of the gradual failure of 
my sight I have not been able to determine the position of 
certain species. I therefore direct the special attention of 
those who adopt my mode of classification, to the mass 
of species included under the section Eupolypodium of the 
" Species Filicum," of which the author says the stipes are 
"articulated upon the caudex, as appears to be all of this 
. group," of which there are 151 described. I have, how- 
ever, failed to identify more than fifty of the species as 
having articulate vernation, and which 1 place under Poly- 
podium as restricted by me, and as far as I have been able 
to determine the many species represented by P. trichoma- 
noides, P. moniliforme, and P. perwiana, have adherent 
vernation, and which I refer to the genus Céenopteris in 
Desmobrya. I also direct special attention to the arboroid 
species of Phegopteris, Lastrea, Goniopteris, and Nephrodium, 
which, on account of their special habit, and the pinnæ 
being articulate with the rachis appears to me of sufficient 
importance to warrant their separation from the more 
humble species of their respective genera. 
The extensive genus Elaphoglossum also presents great 
difference in the nature of its vernation, which appears to 
be of sufficient importance to justify the species being 
arranged in separate generic groups. 
I conclude my general observations on the classification 
of Ferns by saying that my views, like those of other 
Writers, are open to criticism. If the critics have studied 
