*3 
CLASSIFICA TION OF FERNS. 
OPHIOGLOSSACE^E. 
Young- fronds folded up straight, the sori without 
an elastic ring, and 2-valved. 
15. BOTRYCHIUM.—Sori in irregularly branched 
clusters on a separate branch of the frond. 
16. Ophioglossum.—S ori sessile, in 2 -rankedsimple 
spikes on a separate frond. 
In order to facilitate finding the name of a fern, we 
add the following analytical index, for the general 
plan of which we are indebted to Bentham’s admirable 
‘ Handbook of the British Flora.’ 
Fructification in a terminal spike or panicle. The frond either 
leaf-like, or bearing a leaf in the lower part .2 
Fructification in a little cup or involucre at the edge of the frond 
4 
Fructification on the back or under side of some or all the fronds 
5 
Fronds twice-pinnate, usually two or more feet high, the fructi¬ 
fication forming a panicle at their extremity .. Osmunda. 
Fronds stem-like, not 6 inches high, with a terminal spike or 
panicle .. .. . 3 
Spike simple. Leaf entire . Ophioglossum. 
Spike branched into a panicle. Leaf pinnate. Botrychium. 
(Fronds numerous, scarcely 2 inches high, pinnate with few 
deeply lobed segments. Involucre ovate, 2-lobed. 
Hymenophyllum. 
Fronds 6 or 8 inches high, two or three times pinnate, with 
crowded segments. Involucre cup-shaped. Trichomanes. 
Fronds tufted, of two sorts, the centre ones erect, fruiting, the 
outer ones barren, usually shorter, with broader lobes .. 6 
Fruiting and barren fronds similar, or nearly so. 8 
