144 . BRITISH FERNS. - 
leaf-mould, seems best adapted to its requirements: 
it also needs good drainage, and likes to be covered 
with a bell-glass. When successfully grown it is a 
very pretty plant, but I regret to say that its usual 
appearance is shabby and ill-conditioned, 
87. MAIDENHAIR SPLEENWORT. Tricuomanzs. 
Asplenium Trichomanes, Linneus. B. F. 249, 252. 
The radicles are black and wiry; they, insinuate 
_ themselves into the fissures of rocks, previously so 
small as to escape observation: in old buildings this 
fern certainly promotes decay by disintegrating the 
mortar, which, however enfeebled by time, still adds in 
some degree to their strength and durability. The 
fronds make their appearance in April and May, arrive 
at maturity in August and September, and remain per- 
fectly green throughout the winter. The stalk is about 
a third as long as the leafy part of the frond, smooth, 
shining, and, although green at first, eventually be- 
comes nearly throughout its whole length of a pur- 
plish black colour. The frond is narrow, linear, and 
simply pinnate: the pinne are dark green and 
= Very numerous, irregularly ovate, obtuse at the tip, 
and more or less crenate at the margin; they are 
usually distinct and distant, but are sometimes 
_ erowded, and each more or less overlaps the one. 
