See description of C. formosa, a species which should be compared 

 with C. sejuncta. The latter has somewhat larger oogonia and the 

 bracts are always shorter than the mature fruit. 



In hard water lakes and ponds. Wis. 



Chara Schweinitzii A. Braun 1834, p. 353 



PI. 80, Figs. 8-12 



Plants bright green, not at all encrusted with lime, 10-15 cm. high; 

 stem long-jointed, with a single whorl of stipulodes at the node, 

 which also gives rise to 8-11 leaves; internodes of both stem and 

 leaves uncorticated; sex organs monoecious, usually borne on the 

 same node; oogonia 0.8-0.9 mm. long, subtended by bracts which 

 are equal in length to the mature fruit or as much as 3 times longer; 

 cortical cells of oogonium showing 7-9 turns; antheridia 0.28-0.3 

 mm. in diameter. 



Herbarium specimens of this species show a very pronounced 

 translucence or sheen. 



Collected in standing and running water; semi-hard water lakes. 

 Wis. 



Chara vulgaris Linnaeus 1753, p. 1156 



PI. 82, Figs. 1-5 



Plants coarse and brittle, usually much encrusted with lime 

 varies greatly with habitat), variable in height from 4 cm. in 

 shallow water and on sand bars to 40 cm. in deep water on muck 

 bottoms; plants especially odoriferous; stems with diplostichous cor- 

 tication, the secondary laterals wider and more prominent than 

 the primary ( in some varieties the primary and secondary corticals 

 about equal), the node cells of the primary cortical series produced 

 into spines which may vary from mere papillae to very long and 

 prominent cells, giving a distinctly spiny appearance to the plant 

 as a whole (at least in some of the varieties); nodes of the stem 

 bearing a whorl of 6-11 leaves and a double whorl of stipulodes, of 

 which those in the upper series are longer than the lower; leaves 

 uncorticated for 3-4 cell lengths at the tip, the cortications of the 

 leaves ending abruptly at a node which bears 3-6 papillae or 

 thorn-like leaflets of differing sizes; sex organs monoecious, borne 

 on the same leaf node, the subtending bracts about 6, of which 4 

 near the oogonium are longer than the mature fruit, whereas the 

 posterior bracts are very short, even papilla-like; oogonia 0.525- 

 0.8 mm. long, investing cells showing 11-14 or as many as 16 turns; 

 antheridia 0.25-0.55 mm. in diameter. 



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