INTRODUCTION. 
13 
all other Ferns. Their rootstock is smooth, fibrous, and yellow, not creeping nor 
hairy': and gives rise to one or but a few leaves only, which issue from the ground 
with a straight and not circinate vernation. In Botrychium the hud for the 
succeeding year is enclosed in the leaf-stalk of the older leaf, just as is the case in 
the Plane-tree. The leaf divides half way up into two portions, a barren and a 
fertile. The former expands into a blade, either simple (Ophioglossum) or com- 
pound (Botrychium), while the latter forms a kind of spike (Ophioglossum) or 
raceme (Botrychium), consisting of the main veins of the petiole clothed with 
sessile thecae, which are two-valved and quite destitute of an annulus. (See the 
woodcuts to these genera.) The thecae open by a regular transverse fissure, 
emitting smooth, yellow, very minute seeds ; those of Botrychium in twos or 
threes. The rootstocks of both genera are perennial, the leaf-stalks herbaceous 
and hollow. The leaf-stalk of Botrychium has its ducts in two bundles near the 
centre ; that of Ophioglossum in from five to seven bundles ; seated between two 
cylindrical layers, and by their pressure forcing the inner one into a tortuous 
form. 
DISTRIBUTION. — “The two plants comprehended in this small order differ 
from most of the Polypodiaceac, by growing chiefly in more open situations ; 
their upright habit perhaps rendering them less adapted to banks and rocks. 
Both range widely through Britain, and are about equally frequent, holding an 
intermediate place between the rare and the common plants. The Ophioglossum 
prevails chiefly in England, decreasing in frequency northward. The Botrychium, 
on the contrary, is abundant on the hills and moors of the north, and becomes a 
rare plant in the south, and especially in the south-east of England. Ophioglos- 
sum ranges from the south of England, as Devon and Sussex, northward at least 
to Moray ; and, if we may reply upon Barry’s ‘ History of Orkney,’ to those 
islands also. The Botrychium is scarce on the south side of the Thames and 
Bristol Channel, but is stated to grow in North Devon and in Hampshire, though 
not introduced into the Flora of the former county. The stations in the south 
of England of course indicate that both species will grow at a low elevation, and 
remote from the mountain tract, even in the warmest part of Britain ; and both 
also thrive amidst the mountains in the north of England and Scotland ; but the 
Botrychium probably rises to a much greater height on the hills, as it occurs on 
the Breadalbane mountains, near Killin, at the estimated height of 1000 yards, 
whilst no very high elevation for the Ophioglossum appears on record. Of the 
two, the Botrychium is the least frequent, or seems to be so on account of its 
more boreal and Alpine tastes.” — Mr. Watson’s MS. 
EQUISETACEiE. 
( Comprises only Equiseturn.) 
Eq.uisetace.i2, Decan., Ag., Kaulf., Lind., Hook., Grev., Brany. 
Gonopterides, Willd. 
Part of Filices, Miscella.ne.e, &c., of Authors. 
