158 
ASPIDIACEiE. 
Closely allied to the first of these is a small and beautiful va- 
riety found by Mr. Gibson, at Burnley, near Coin, in Lancashire ; 
the figures at page 149 faithfully represent some fronds presented 
to me by Mr. Gibson. This variety produces abundance of seed, 
the clusters of capsules becoming confluent, and occupying 
the entire under surface of the frond. It should here be ob- 
served that Roth makes no less than six species of this genus, 
five of which appear to be referrible to the plant now under 
consideration.* 
It is almost impossible to give a satisfactory description of a 
fern so variable in form. 
The roots are numerous, black, wiry ; the rhizoma is tufted. 
The fronds begin to unfold early in the spring, and appear very 
evanescent, generally arriving at maturity in a few weeks : a 
constant succession of fronds is produced throughout the sum- 
mer and autumn, but all disappear with the first frosts of winter. 
The general form of the frond is lanceolate and pinnate ; the 
pinnae are also pinnate, but beyond this they appear to possess 
no character in common. The length of the stem is very various. 
The lateral veins are alternate, and each is usually divided into 
three or four branches, one extending to every serrature in each 
lobe of the pinnule. The lower detached figure in page 155 re- 
presents a pinnule, showing the veins and points of the attach- 
ment of the capsules ; the figure immediately above it represents 
a lobe of the same pinnule ; almost every vein bears a cluster 
of capsules near its extremity ; the cluster is nearly circular, 
and has a loose, white, membranous involucre, attached on 
one side only, beneath the capsules ; its margin, at the farthest 
extremity from its attachment, is striated, and becomes split into 
capillary segments, or sometimes torn in a ragged manner, and 
at length entirely disappears : the clusters of capsules rapidly 
increase in size, frequently becoming confluent, as represented 
at page 154, where the apex of a frond with confluent clusters 
is represented to the left of the cut. In cultivation I have ob- 
served that sometimes, from the plant receiving a check from 
exposure or improper treatment, the masses remain of small size, 
and covered with the involucre, even after the frond has withered. 
^ Roth, Flor. Germ. iii. 93. See Appendix E. 
