172 NOTES ON DESMARESTIA PINNATINERVIA, 
species to be inquired about; but in his note to D. Vujulata^ he states 
that lie believes D. pinnatinervia and D. Dremayi are a broad form of 
the European D, Ugtilata, ^ 
The Cornish specimen justified^ and^ I think, goes far to establish 
the validity of this theory; for the specimens were found growing 
from the same root as the typical English form of Desmarestia Ugti- 
lata^ and if the frond is compared with the thin young state of that 
plant, and especially with the broad membranous variety of it found in 
Cornwall, and on the west coast of France and Spain, there is no 
structural difference to separate them, — the oidy reid difference being 
that the frond is much wider, and^ for its size, comparatively thinner 
and more membranaceous, and, in those which I have seen, like that 
figured by Montague and described by Crouan, the frond was simple, 
not proliferous on the edge, looking very like afrondof P^^wc/flr^'a lati- 
foliaj with a dentated edge, and a very slender midrib, with opposite 
veins, 
I am not inclined to regard it as a variety of i). ligulatay but as 
a particular development of some of the fronds of that species^ for I 
am informed that it absolutely grows from the same root-disk, and 
that many of the roots have one or more such fronds developed along 
with the usual narrow state of that plant. 
This broad and simple form of the frond, from the foregoing ob- 
servations, seems to have been observed on the coast of Spain, France, 
Ireland, and Cornwall. It is very desirable that some collectors 
on the coast of Cornwall or Ireland should study the development 
of these fronds, and the circumstances under which they are deve- 
loped ; for it must be admitted that growing apparently from the same 
root is not an infallible sign of plants being the same, without we are pre- 
pared to admit that Desmarestia ligulata and Desmarestia viridis are the 
different states of the same plant, for in Wales I have more than once 
found these two plants growing apparently from the same root-disk, 
unless I have mistaken what Mr. Turner calls a variety of D. ligulata 
for D. viridis, for as Dr. Harvey observes, *'In other states the fronds 
are so narrow, that, as Mr. Turner well observes, such individuals may 
at first sight be mistaken for luxuriant fronds of D. viridis, whose 
numerous varieties are as delicate as the finest Con/ervce,^^ 
Notwithstanding the observation with which Dr. Harvey commences 
his account of D, viridis, that "there are no British Al^se with which 
