. The Characeae of America. Characeae. Plate I. CHARA GYMNOPUS, A. Br. Var. elegans, A. Br. Sub-order, Verticills of leaves mostly surrounded by a whirl of stipules. Leaves many-celled, with bract-bearing nodes. Bracts one-celled, shorter than the leaf. Antheridium lateral occupying the place of a bract, on the inner (ventral) aspect of the leaf, usually single. Sporangium on ventral aspect of leaf. Coronula of sporangium consisting of a single series of five cells, persistent. Genus, Chara. Sporangium arising from the uppermost cell of the basilar node of an antheridium or a correspon
. The Characeae of America. Characeae. Plate I. CHARA GYMNOPUS, A. Br. Var. elegans, A. Br. Sub-order, Verticills of leaves mostly surrounded by a whirl of stipules. Leaves many-celled, with bract-bearing nodes. Bracts one-celled, shorter than the leaf. Antheridium lateral occupying the place of a bract, on the inner (ventral) aspect of the leaf, usually single. Sporangium on ventral aspect of leaf. Coronula of sporangium consisting of a single series of five cells, persistent. Genus, Chara. Sporangium arising from the uppermost cell of the basilar node of an antheridium or a corresponding bract, hence axillary. * Diplostei'HAN/E. Whirl of stipules developed from a double series of cells, stem always corticated ; leaves usually so. * * Cortex uniformly developed around the stem; the series of cells approximate leaving no interspaces. * * * Gvmnopodes. First basal internode of the leaf naked, not corticated ; other internodes triple-corticated. * * * * Antheridia and sporangia borne on the same leaf; in one species {sejmuta) on different nodes. Chaka Gymnopus. This species has been established, by the late Prof. Braun, to include a large number of closely related forms from all parts of the world; and we are inclined to extend it so as to embrace all the monoecious Gymnopodas. The variation in size of plant, size and shape of sporangium, development of bracts, length of the naked basal internode (very short in some American varieties, var. HumbolJtii, etc. ; very long in Ch. Angolensis , and in Ch. Robbinsii. Halsted), number of corticated internodes, and of naked terminal internodes, development of the coronula, etc., is very great, and no satisfactory line can be drawn. Prof. Braun remarks in Characecv Africans " So long as I knew but few forms of the Gymnopodce, their distinction seemed easy ; but when it became necessary to determine sixteen to eighteen forms, I concluded to consider them all varieties of a single species, f
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