. Scolopendrium. |] XOIV. FILICES. 565 
1. S. vulgare, Sm. (fig. 1300). Common Hart’s-tongue.—F¥ronds 
tufted, undivided (except in monstrous forms), broadly linear or narrow- 
oblong, cordate at the base, with rounded auricles, usually about a foot 
long and 13% to 2 inches in the broadest part, of a firm consistence, smooth 
and shining on the upper surface, with a brown or greenish foot-stalk of 
about 2 to 4 or 5 inches, Sori numerous, transverse and parallel, in 2 rows, 
one on each side of the midrib, usually of very different lengths, but never 
reaching cither to the midrib or to the edge of the frond. 
On shady banks, rocks and walls, in ravines, etc., in temperate and 
southern Europe, west central Asia, Japan and North-west America, ex- 
tending from the Mediterranean to the Baltic. Common in Britain. F’7. 
the whole season. It varies much in size from 6 inches to near 2 feet, and 
in the fantastic forms assumed by the barren fronds when monstrous, 
especially under cultivation. No less than 58 of these forms are named in 
Moore’s Handbook. 
X. CETERACH. CETERACH. 
Fronds pinnatifid or pinnate. Sori linear and diverging as in Asplenium, 
but without any distinct indusium, and usually almost concealed under the 
scales of the under surface of the frond. 
The genus is now limited to the European species and a second larger 
one from the Canary Islands. 
], C. officinarum, Desv. (fig. 1801). Scaly Ceterach.—¥Fronds tufted, 
Spreading, about 2 to 6 inches long, deeply pinnatifid or pinnate, with 
broadly oblong or rounded lobes or segments attached by their broad base, 
green and glabrous on the upper side, but the under side thickly covered 
with brown scarious scales, which completely conceal the sori until they 
become very old. <Asplenium Ceterach, Linn. 
On rocks and old walls, in central and southern Europe and west cen- 
tral Asia, extending northward to Holland. In Britain, common in many 
parts of England, especially western, and in Ireland and western Scotland. 
Fr. summer and autumn. 
XI. BLECHNUM. BLECHNUM. 
Sori linear, one on each side of the midrib of each segment and parallel 
to it. Indusium attached along the outer edge of the sorus, opening out- 
wards from the inner side. 
A small genus, spread over many parts of the world, but chiefly 
tropical. 
1. B. Spicant, Roth. (fig. 1802). Hard Blechnum.—Fronds simply 
pinnate, tufted, of two kinds, the outer barren ones spreading, usually 6 
inches to near a foot long; the segments lanceolate, curved, entire, 
attached by their broad base; those in the centre of the frond 1 to 13 inches 
long, gradually decreasing towards each end. Fruiting fronds in the 
centre of the tuft, erect, 1 to 14 feet high; the segments of the same 
length as in the barren ones, but all narrow-linear ; the under side entirely 
occupied by the 2 linear sori. B. boreale, Sw. Lomaria spicant, Desv. 
In woods, and rather moist stony places and heaths, generally distributed 
