

160 THE BRITISH FERNS. 
costa is ramose below or multifid near the apex; or sometimes a 
rounded lobe like an arrested branch protrudes from the margin. 
The base is truncate, and the apex usually divided, while the margin 
is deeply incised so as to form unequal lobes, which are evenly 
toothed, producing a fimbriate appearance; the margins both of the 
undivided portion and of the multifid apex are also slightly undu- 
lated or corrugate. The fructifications are copious but irregular. 
It was found in Ireland by Dr. Allchin, in 1853. 
36. furcans (M.). A dwarfish form cordate at the base, and 
forked once or oftener at the apex, sometimes divided into a tuft of 
five or six lobes; the margin is unequally crenate-lobate. The 
veins are rather close and sometimes coalesce; and a few pale 
yellowish streaks appear on the surface. Itis a fertile form, found 
by Mr. Elworthy in Somersetshire. 
37. limbospermum (M.). A curious variety, with thick coriaceous 
fronds eight or ten inches long, upwards of an inch wide near the 
base, narrowing upwards and becoming forked at the point, or a 
little below, with the branches forked at their tips. The base is sub- 
truncate, and the margins are somewhat irregular with projecting 
lobes, which often point forwards so as to take the form of coarse 
serratures, the whole being obscurely toothed. The fructification 
is peculiar ; the sori are very short and close to the margin, in many 
places dot-like and attached to the extreme edge, the dots some- 
times confluent so as to bring the spore-cases into a narrow irregular 
marginal line; some sori are also produced on the upper surface. 
It was found near Nettlecombe by Mr. Elworthy, who describes 
all the fronds to be alike as regards the fructification. 
38. curtum (M.). This form has thick fronds with confused or 
muddy-leoking tissue as in Zurgidum (72); they are variable in 
form, sometimes nearly normal, with the apex dentate, sometimes 
contracted and truncate at the base, more or less lobed at the 
margin, abrupt lobate or abruptly ramose, often abbreviated at the 
apex, here and there subcontraeted and supralineate. It was found 
in Somersetshire by Mr. Elworthy. 
39. inops (M.). This variety bears elegant narrowish fronds six 
or eight inches long, cordate at the base, irregular, somewhat lobed, 
and throughout crenate-dentate at the margin, the apex forked; or 

