THE 
GENERA AND SPECIES OF CULTIVATED FERNS. 
Order, POLYPODIACE^, E. Beown. 
Tribe, Polteodie.®, J. Smith — Sori of definite form, naked, i. e. without an indusium. 
Sect. ORTHOPHLEBIE.E, J. Smith (from orthos, straight, and phleps, a vein). — Veins simple or forked, free, that is, not 
united so as to form a network. 
I. GEAMMITIS, Swartz. 
Sori oval, oblong, oblique ; spore-cases lateral. Veins simple or forked, internal, the soriferous 
venule sometimes very short. Fronds simple, hncar, with entire or serrulate margins, plane or con- 
vex at the apex. — Name derived from pramme, a line ; alluding to the lines of sori. 
This genus has considerable affinity with the %Leptogramma of Oymnogr amnia, in 
consequence of its linear-oblique sori ; but it is distinguished by its dwarf habit, simple 
fronds, and more simple venation. There are several species known; but one only has 
hitherto been introduced in a living state. Fig. 1 represents the upper portion of a frond 
of Grammitis Billardieri (nat. size). 
1. G. Billardieri, Willdenow {G. australis, 5. i?roM;w). — An interesting evergreen greenhouse 
species, from New Holland. Fronds simple linear-lanceolate acuminate, from four to six inches long, 
light green, attenuated at the base. Sori linear-ohlique, confined to the upper portion of the frond, 
occupying the whole of the venules. Stipes hairy ; terminal, adherent to a tufted rhizome. 
II. POLYPODIUM, Linneeus. 
Sori circular, rarely oval or oblong, naked, transverse, uniserial, solitary or irregular; 
spore-cases terminal or lateral, sometimes seated in a deep cyst or cavity forming elevated 
protuberances on the upper surface of fronds. 
Veins simple, forked or pinnate, free. Fronds varying from 
a few inches to four or five feet high, and from simple to 
decompound ; coriaceous, membranous, glabrous, villose or 
glandulose. — Name derived from 2>olys, many, and iious, a 
foot ; the creeping rhizome having many foot-like divisions 
or tubercles. 
This genus, before it was divested of those possessing a 
reticulated venation, included between 200 and 300 species, 
presenting wide differences in habit and texture and in the 
circumscription of their fronds, which arc now distributed 
among nine genera. The true Polypodiunis have naked circular (rarely oblong) sori, with simple 
Ibrked or pinnate free veins. Fig. 2 represents a portion of Polypodium vulgare (nat. size). 
Fig. 1 
