(1) Rusty Woodsia. Woódsia Ilvénsis
Fronds oblong-lanceolate, three to ten inches high, rather smooth above, thickly clothed underneath with rusty, bristle-like chaff. Pinnate, the pinnæ crowded, sessile, cut into oblong segments. Fruit-dots near the margin often confluent at maturity. Indusium divided nearly in the center into slender hairs which are curled over the sporangia. Stipes jointed an inch or so above the rootstock.
The rusty Woodsia is decidedly a rock-loving fern, and often grows on high cliffs exposed to the sun; its rootstock and fronds are covered with silver-white, hair-like scales, especially underneath. These scales turn brown in age, whence the name, rusty. As the short stipes separate at the joints from the rootstock, they leave at the base a thick stubble, which serves to identify the fern. Exposed rocks, Labrador to North Carolina and westward. Rather common in New England. Said to be very abundant on the trap rock hillocks about Little Falls, N.J., where it grows in dense tufts.