. Our native ferns and their allies [microform] : with synoptical descriptions of the American pteridophyta north of Mexico. Ferns; Fougères. V,, THE FERN ALLIES, 29 In Ophioglossum or short stalked, in the various species, the sterile portioti is simple, and in all our species appears like a leaf rising *rom the common stalk. C/tet'roji^l>>ssa has several spikes. In Botrychium (Fig. 19) the sterile segment (except in some forms of B. simplex) is somewhat pinnatcly or ternately divided, and in the larger forms of B. Virginianum is broad- ly ternate, with the divisions even tri—quadripinn
. Our native ferns and their allies [microform] : with synoptical descriptions of the American pteridophyta north of Mexico. Ferns; Fougères. V,, THE FERN ALLIES, 29 In Ophioglossum or short stalked, in the various species, the sterile portioti is simple, and in all our species appears like a leaf rising *rom the common stalk. C/tet'roji^l>>ssa has several spikes. In Botrychium (Fig. 19) the sterile segment (except in some forms of B. simplex) is somewhat pinnatcly or ternately divided, and in the larger forms of B. Virginianum is broad- ly ternate, with the divisions even tri—quadripinnatifid. The veins are free in the latter genus, but anas- tomose in the former. This charac- ter, however, is frequently obscured by the fleshy texture of the plant. 83. Vernation.—As has been before stated, ferns are rolled in the bud from the apex downward («>- a'nate), distinguishing them from the higher forms of vegetation. Among the OPHiOGLOSSACEiE, how- ever, the vernation is either straight, inclined at the apex of one or both segments, or else the fertile seg- ments are folded on the main stalk, making the vernation wholly in- clined. Until recently there has been much difficulty in distinguishing the smaller species of Botrychium, and some forms seem to connect the smaller ones with the reduced forms of B. obliquum and B, Virgini- anum. Mr. Davenport has investigated the bud characters of these intimately related species, and has made their identification a matter of comparatively easy investigation. The buds may be found enclosed in the base of the common stalk (except in B. Virginianum^ where they are placed in an upright cavity at one. "-*i Fig. 19.—Plant of Botrychium lunaria^ natural 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 Underwood, Lucien Marcus, 1853-1907. New
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