. The origin of a land flora, a theory based upon the facts of alternation. Plant morphology. SCHIZAEACEAE 543 to a dichotomous branching is not so clear. In the former the lowest pair of pinnae are usually fertile, in the latter genus the sporangia may be distributed over the whole length of the leaf. Hairs are present in all the genera, and in all except Mohria they are filamentous, as in the Botryopterideae, Marattiaceae, and Osmundaceae,. Fig. 300. Upper parts of fertile leaves of the genus Schizaea. A ~Sch. pennula, Sw. B=Sch. bifida, Sw. C, D=Sck. elegans, J. Sm. In D the ultimate segmen
. The origin of a land flora, a theory based upon the facts of alternation. Plant morphology. SCHIZAEACEAE 543 to a dichotomous branching is not so clear. In the former the lowest pair of pinnae are usually fertile, in the latter genus the sporangia may be distributed over the whole length of the leaf. Hairs are present in all the genera, and in all except Mohria they are filamentous, as in the Botryopterideae, Marattiaceae, and Osmundaceae,. Fig. 300. Upper parts of fertile leaves of the genus Schizaea. A ~Sch. pennula, Sw. B=Sch. bifida, Sw. C, D=Sck. elegans, J. Sm. In D the ultimate segments are more strongly magnified. (After Diels, from Engler and'Prantl, Nat. Pflanztnfam.~) and are sometimes glandular. In Mohria they are no longer filamentous, but flattened as scales : this condition, which is characteristic of most Ferns of a more advanced type, is readily referable in origin to lateral widening accompanied by longitudinal cell-divisions. The sporangia are not arranged in sori, but solitary, a number of them being borne on each fertile segment. In Schizaea and Aneimia they appear when mature disposed in regular rows, one on each side of the midrib, on the lower surface of the fertile segments. They may be protected. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Bower, F. O. (Frederick Orpen), 1855-1948. London, Macmillan and Co. , Ltd.
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