FAMILY I, FILICES Juss. 
F LOWEBLESS plants, circinate in vernation ; leaves usually 
much divided, raised on a stalk, some or many of them 
bearing on the under surface or along the margins of the 
divisions, small spore cases (sporangia), which are often collected 
in clusters (sori) and contain very many minute spores, all of one 
kind ; fertile fronds, or their fertile portions, sometimes much con- 
tracted and changed in appearance, causing the sporangia to ap- 
pear as if in panicles or spikes. In the following descriptions, the 
frond is considered to include both leaf and §talk, and the leafy 
portion to be the lamina ; the stipe is the portion of the frond be- 
tween the rootstalk and the lamina, an(j the rachis its continua- 
tion through it. 
Sub=Family i, PoSypodiacese Presl. 
Sori, either on the dorsal side of the lamina collected in clusters 
or forming lines along the edge of its divisions. Sporangia 
surrounded by vertical, elastic rings, bursting tranversely 
and scattering the spores. 
Tribe IT, POLYPODIES. 
Kepresented by a single genus, and with us by a single species. 
POLYPODIUM L. 
V 
2. P. vulgare L. Polypody. Fronds 4-12 inches long ; lam- 
ime 1-3 inches wide, nearly pinnate ; sori collected in large, brown- 
isn-yellow dots, with no indusia. Evergreen. Aug -Dec. Every- 
where common on cliffs and rocks, usually in half shade. Europe, 
Japan, etc. 
