76 
HISTORY OF BRITISH FERNS. 
teristic is very obvious, for the three branches appear 
rolled up separately at the tips of three little wire-like 
stalks, supported by one which is longer and stouter. It 
is a slender and delicate plant, its height being commonly 
not more than six inches, often less, though sometimes 
more; and its texture is fragile. Hence, it is at once 
destroyed by frost, and soon becomes rusty and withered 
by exposure to heat and drought. When growing in a 
cool, shady situation, however, it continues fresh and 
cheerful-looking from April, when it usually starts into 
growth, onwards until it is affected by autumnal cold. In 
pots, in Wardian cases, or on sheltered shady rockwork, it 
is alike desirable for cultivation. 
The fronds of this delicate little Fern grow from a 
slender creeping stem, which often forms densely matted 
tufts. They are quite smooth, and of a bright light green 
■colour, supported by stipes which are usually about twice 
as long as the leafy part, and are slender, brittle, and dark- 
coloured. The outline is almost pentagonal, the frond 
being divided into three branches, each of which is of a 
triangular form One peculiarity about this species, which 
is in a slight degree shared by its near ally P. Robertia - 
num, is the deflection of the rachis at the point where the 
