SCOLOCHLOA.—(1) Inflorescence of S. festucacea, reduced; (2) a spikelet, enlarged; and (3) a flower.
PUCCINELLIA.—(1) Inflorescence of P. maritima, reduced; (2) a spikelet, enlarged; and (3) a flower.
POLYPODIUM.—Plant of P. vulgare; piece of the frond; a magnified sporangium with its stalk, and another bursting and discharging spores.
ONOCLEA.—(1) Pinna of the sterile frond of O. Struthiopteris; (2) portion of a fertile frond; (3) a piece of one pinna cut off to show the manner in which it is rolled up; and (4) a portion of the last, magnified, with one side unrolled; toward the base the sporangia all removed, to show how the fruit-dots are borne each on the middle of a vein.
PELLÆA.—Sterile and fertile plants of P. gracilis, and (1) a portion of the fertile frond enlarged, with a piece of the marginal indusium turned back to display the fruit; the sporangia are all removed from the fruit-bearing tips of the two forks of the lower vein.
