

54 THE BRITISH. FERNS. 
peculiarity—namely, that the veins branch out from a central rib, 
and are free or disunited at their apices, that we cannot adopt the 
views of those who would separate them. 
The fructification of Polypodium, it has been already stated, consists 
of round or dot-like masses of spore-cases. In some species these 
are developed at the tips of the veins, the receptacle or point of 
attachment being either small and punctiform, or dilated into an 
obovate form. The terminal-fruited British species has the veins 
rather divergently forked, and those which are not fertile are tipped 
by a club-shaped or thickened point, which is often visible on the 
` upper surface, forming a line of slightly sunken dots which are 
occasionally white with a kind of cretaceous exudation. In other 
species the receptacles are produced on the back of the veins, at a 
greater or less distance from their point, these forming the medial- 
fruited group. The veins in the latter group do not terminate in 
club-shaped apices, and the sori though usually round and dot-like, 
are occasionally somewhat elongated. 
Mr. Newman, adopting what he calls the rhizophyllaceous and 
the cormophyllaceous groups of annulate ferns, which mode of 
grouping he admits to be “a division which literally halves” such 
genera as Polypodium and others, carries his notion to an extreme 
point by discarding altogether the name of Polypodium, and impo- 
sing three new ones. Thus he proposes Ctenopteris as the name of 
the common Polypody, the old name of which, in any case, should 
be held sacred ; whilst Gymnocarpium is provided for P. Phegopteris 
and its allies; and Pseudathyrium for the plants represented by 
P. alpestre. Ctenopteris had already been suggested as a sectional 
group of Polypodium, and to this there can be no reasonable objec- 
tion; and the group indicated by G’ymnocarpium had been also 
proposed as another section under the name of Phegopteris. This 
latter name is adopted for the plants referred to the Gymnocarpium 
and Pseudathyrium of Newman, by the majority of those pteri- 
dologists who admit the generic importance of the group. 
The genus Polypodium, with the limits already indicated, is a 
large group scattered over the whole world, and containing numerous 
species which are separable into about half-a-dozen sections, two 
only of which are represented among British Ferns. These two 

