. The Characeae of America. nodes of old stems become swollen and filled with granules of starch. Fig-. 33 represents a subter- ranean node of Ch. fragilis3 with the basal nodal cells rilled with starch granules; not only are they deposited in these cells, but in the internodal cells of leaf and stem, as well. When a new shoot arises from an axil of this plant, this store of nutriment is drawn upon till the new plant attains size enough to enable it to appro- priate its own food. Fig. 34 represents a tuft of minute radicles enlarged at their tips and filled with starch, so that they look like
. The Characeae of America. nodes of old stems become swollen and filled with granules of starch. Fig-. 33 represents a subter- ranean node of Ch. fragilis3 with the basal nodal cells rilled with starch granules; not only are they deposited in these cells, but in the internodal cells of leaf and stem, as well. When a new shoot arises from an axil of this plant, this store of nutriment is drawn upon till the new plant attains size enough to enable it to appro- priate its own food. Fig. 34 represents a tuft of minute radicles enlarged at their tips and filled with starch, so that they look like a bunch of white grapes; each bulblet is nearly round and one-celled; drawn from Ch. aspera. Pringsheim (ueber die Vorkeim und die nacktfuessigen Zweige der Charen, Jahrb. f. Botanik, 3, 294), has studied the reproduction of Ch. fragilis from old stem nodes, by means of gymnopodal shoots (naked footed), which are imperfectly developed at the base, but which subsequently become perfect stems; and, also, by means of protonemal shoots, which, at first rudimentary, give rise to perfect stems by a lateral growth, behaving, in this respect, just like the first growth of the seed, the seed Fig- 34- ORGANS OF FRUCTIFICATION.—The Antheridia and Sporophydia are always borne on the leaves or on their basal nodes. Antheridia, the male organs, producing spermatozoids, are always metamorphosed terminal segments of leaves, or of their lateral rays (bracts}; Sporo- pliydia arise from the same node, but lateral to the Antheridia. In Chara the Antheridium occupies the place of a bract on the side of a leaf, and the sporophydium arises from one (the upper) of the basilar cells; if the species be dioecious the sporophydium occupies the same position in relation to the bract. In Nitella the Antheridium is termi- nal (on the end of the leaf), and the sporophydium arises from one of. Please note that these images are extracted from scanned page images that may have been digitally enhanc
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