Cystopteris -Key to the Genus


Fertile fronds distinctly widest at the base, tapering into long, slender tips; bulblets borne along the rachis and pinnae in late summer, usually on the lower side of the frond; rachis, midribs of fronds and pinnae, and indusia densely glandular-hairy; veinlets ending in the notches between the teeth of the pinnae.


Fertile fronds slightly narrowed toward the base, not prolonged into slender tips; bulblets absent; glandular hairs absent; veinlets extending into the tips of the teeth of the pinnae.