FORKED SPLEENWORT. 
273 
want the mesian nerve or midvein, which is always present in 
the rest : hence the group might perhaps be called Amesium. 
The roots are very long, fibrous, crooked and intertwined, and, 
together with the rhizoma, which is very large and tufted, form 
an amazing bulk. 
The fronds make their appearance in March and April, arrive 
at maturity in August, and remain green throughout the winter ; 
they grow in a horizontal position from a perpendicular surface. 
The fronds represented at page 269 are in the natural position. 
The form of the frond is elongate, lanceolate, and furnished late- 
rally with one or two short bifid teeth or serratures, and the apex 
also terminates in a bifid point : it diminishes imperceptibly to- 
wards the base, and there terminates in a smooth stem, which is 
black at the extreme base. 
The veins are nearly simple, and 
into each serrature. The capsules 
a continuous line, covered at first 
by an involucre of similar shape, 
which opens towards the middle 
of the frond, and, as the capsules 
swell, is thrown back, and finally 
lost, and the lower surface of the 
nuous mass of capsules. 
Roth describes the involucre as double,^ but this, although 
Ohserv. I. Foliolum (vel lacinia) fructiferum lineis duabus plerumque, 
in prona pagina depressis et exaratis, in aversa elevatis prseditum est. Duabus 
hisce elevatis lineis, qua vero neutiquam nervi sunt, paginse aversae affiguntur 
capsiilae secundum longitudinem, numeros®. Inter has lineas capsuliferas et 
marginem oritur Involucrum duplex, longitudinale, continuum, membranace- 
um, tenuissimum, albidum, valvulis in medio secundum longitudinem ante 
maturitatem arete sibi incumbentibus et capsularum duplicem seriem arete in- 
cludentibus. Hoc in conspectum veniet cuique observatori, quando laciniam 
frondis fructiferam, involucre adhuc tectam, dorso lineam depressam inter et 
marginem longitudinaliter findat. Maturescentibus capsulis magisque elevatis 
involucrum secundum totam longitudinem in medio dehiscit, quod ob copiam 
capsularum cum elasticitate sese effundentibus, non raro rupturas transversales 
irregulares patitur. Replicatis tunc involucri valvulis effusse capsulee totam la- 
ciniae inferiorem paginam obducunt et ita Acrostichi speciem mentitur planta, 
quae verum est Scolopendrium.' — Roth, Flor. Germ. iii. 50. 
few in number, one running 
are attached to each vein in 
frond then presents a conti- 
T 
