BRITTLE FERN. 
155 
The second variety I consider to be the typical form of P, 
fragile^ as described by Linneus. 
Cystea fragilis. Smith. '' Fronds several together, from four to 
ten or twelve inches high, lanceolate, 
pointed, smooth, of a full though bright 
green, doubly or almost triply pinnate. 
Stalk brown or blackish, very brittle 
and juicy, occupying one- third or near- 
ly half of the length of the whole, des- 
titute of scales, except at its very base. 
The primary divisions or leaves are usu- 
ally nearly opposite, acute, of a moderate 
length ; leaflets mostly alternate, ovate, 
acute or pointed, in barren fronds some- 
times blunter ; their base always tapering 
and decurrent ; they are by no means 
linear or oblong, nor is their margin 
wavy, but copiously, deeply and sharply 
toothed, and their substance is firm ; the 
larger and lower ones are deeply pinna- 
tifid, their lobes resembling the upper 
leaflets. Masses numerous and crowd- 
ed, globular ; at first pale^ but finally 
blackish and confluent, covering the 
whole back of the frond. Cover 
white, flaccid, membranous, concave, 
irregularly jagged and torn, sometimes 
lengthened out into an oblong point, but 
soon turned back and obliterated, or 
forced off by the swelling, shining cap- 
sules, which, in an early state, are often 
quite black, though subsequently brown- 
erf"^ In this description a discrepancy 
occurs in the colour of the capsules ; the colour of the clusters, 
in an early state, is very inconstant, but generally blackish ; the 
autumnal fronds, when in cultivation, have smaller clusters than 
* Eng. Flor. iv. 286. 
