On moist, mossy, mostly calcareous rocks, northern New England, Mount Mansfield, Willoughby, and Bakersfield Ledge, Vt., Gorham, N.H., also Newfoundland, New York, and far to the northwest. Not very common. It differs from the alpine species by the absence of scales above the joint. As the name implies, the plant is smooth, except for the chaffy scales at or near the rootstock, which mark all the Woodsias, and many other ferns, and which serve as a protective covering against sudden changes in extremes of heat and cold.

(5) OREGON WOODSIA. Woódsia oregàna

Fronds two to ten inches high, smooth, bright green, glandular beneath, narrowly lance-oblong, bipinnatifid. Pinnse triangular-oblong, obtuse, pinnatifid. Segments ovate or oblong, obtuse, crenate, the teeth or margin nearly always reflexed. Indusium minute, concealed beneath the sorus, divided into a few beaded hairs.

Like the obtuse Woodsia this fern has no joint near the base of the stipe, but is much smaller and has several points of difference. Limestone cliffs, Gaspé Peninsula, southern shore of Lake Superior, Colorado, Oregon to the northwest. Its eastern limit is northern Michigan.

(6) ROCKY MOUNTAIN WOODSIA. Woódsia scopulìna

Fronds six to fifteen inches long [smooth], lanceolate, pinnatifid. Pinnæ triangular-ovate, the lowest pair shortened. Under surface of the whole frond hispidulous with minute, white hairs and stalked glands. Indusium hidden beneath the sporangia, consisting mostly of a few hair-like divisions.

In crevices of rocks, mountains of West Virginia, Gaspé Peninsula, Rocky Mountains, and westward to Oregon and California.

(7) CATHCART'S WOODSIA. Woodsia Cathcartiàna

Fronds eight to twelve inches high, lanceolate, bipinnatifid, finely glandular-puberulent. Pinnse oblong; the lower distant segments oblong, denticulate, separated by wide sinuses.

Rocky river banks, west Michigan to northeast Minnesota.