The Fern Family Proper or Real Ferns
Polypodiàceæ
Green, leafy plants whose spores are borne in spore-cases (sporangia), which are collected in dots or clusters (fruit-dots or sori) on the back of the frond or form lines along the edge of its divisions. Sporangia surrounded by vertical, elastic rings bursting transversely and scattering the spores. Fruit-dots (sori) often covered, at least when young, by a membrane called the indusium. Spores brown.