Page:Parsons How to Know the Ferns 7th ed.djvu/172

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GROUP V

FERTILE AND STERILE FRONDS LEAF-LIKE AND SIMILAR;
SPORANGIA IN LINEAR OR OBLONG FRUIT-DOTS

The known stations of this curious little plant are usually in the immediate neighborhood of the Walking Leaf and the Ebony Spleenwort, of which ferns it is supposed to be a hybrid. The long, narrow apex occasionally forming a new plant, and the irregular fruit-dots remind one of the Walking Leaf, while the lustrous black stalk, the free veins, and the pinnate portions of the fronds suggest the Ebony Spleenwort.

Scott's Spleenwort matures in August. It is rare and local, except in Alabama. The fact, however, that it has been discovered in widely distant localities east of the Mississippi should lend excitement to fern expeditions in any of our limestone neighborhoods where we see its chosen associates, the Walking Leaf and the Ebony Spleenwort. To find a new station for this interesting little fern, even if it consisted of one or two plants only, as is said to have been the case at Canaan, Conn., would well repay the fatigue of the longest tramp.

32. PINNATIFID SPLEENWORT

Asphnium pinnatifidum

New Jersey and Pennsylvania to Illinois, and southward to Alabama and Arkansas, on rocks. Four to fourteen inches long, with polished stalks, blackish below, green above, when young somewhat chaffy below.

Fronds.—Broadly lance-shaped, tapering to a long, slender point, pinnatifid or pinnate below; pinnæ rounded or the lowest tapering to a point, fruit-dots straight or somewhat curved; indusium straight or curved.

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