. The Characeae of America. II by its somewhat broader or truncated appearance ; in many species the two ends can scarcely be distinguished. The nucleus of some species, for example, Chara intermedia, becomes densely incrusted (like the stem) with a deposit of lime, which seems to be imbedded in a delicate soft hyaline matrix; this deposit must be dissolved by a dilute acid before the nucleus can be studied. GERMINATION.—The germination of the Characeae has been exam- ined by Vaucher*, Kaulfussf, Bischoff|, Pringsheim§, Nord- stedt|| and A. de Bary^[. To Pringsheim belongs the credit of having
. The Characeae of America. II by its somewhat broader or truncated appearance ; in many species the two ends can scarcely be distinguished. The nucleus of some species, for example, Chara intermedia, becomes densely incrusted (like the stem) with a deposit of lime, which seems to be imbedded in a delicate soft hyaline matrix; this deposit must be dissolved by a dilute acid before the nucleus can be studied. GERMINATION.—The germination of the Characeae has been exam- ined by Vaucher*, Kaulfussf, Bischoff|, Pringsheim§, Nord- stedt|| and A. de Bary^[. To Pringsheim belongs the credit of having discovered the true character of the first outgrowth of the spore, but Nordstedt first clearly and accurately traced, step by step, the whole process; this work, published in Swedish, not being acces- sible to students generally, was reviewed and enlarged by the inves- tigations of Prof, de Bary. From these authors our account and illus- trations of the process are taken. As germination is about to commence, the granules of fat and starch in the upper part of the oospore give place to finely granular protoplasm (Fig. i, a de-calcified nucleus of Ch. fcetida, A. Br., n). This partially clear spot fills the upper end and has the form of a plano-convex lens, with its convex- ity upward and its plane surface pressing against and clearly sepa- rated from the remaining contents of the cell. Along this line of de- Fig, i. marcation a septum forms, which divides the oospore into two cells, the smaller upper one, the first no- dal cell, from which all growth proceeds, and the larger lower basal cell filled with fat and starch, the reserve material for nour- ishing the germinating plant. The upper cell enlarges and splits the shell along the line of its angles into five parts ; it then pro- trudes a little into the water and undergoes fissation, by. a vertical * Mem. de la Soc. d. Phys. de f Erfahrungen ueber das Keiinen der Charen, Leipzig, 1825. JDie Crypt. Gewachse,
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