. Plant life, considered with special references to form and function. Plant physiology. 28o PLAXr LIFE. l)Ut the seed piaiits was desrribed in Part I. 'I'he forms of the spermaries are as iolhiws : 383. Chara.â'I'he compound siiermary of Chara (fig. 313) consists of a splierical case comijosed of fmr triangular, plate-Uke cells ; from the inner face of eacli projects a handledike cell to whose end are attached 24 filaments, each composed of 100-200 disk-shaped cells. I'^ach of these con-. Fig. 312.âDevelopment of a sperm of a liverwort {PcIUa e/>i/'hyila\. n, mother cell with nucleus, the
. Plant life, considered with special references to form and function. Plant physiology. 28o PLAXr LIFE. l)Ut the seed piaiits was desrribed in Part I. 'I'he forms of the spermaries are as iolhiws : 383. Chara.â'I'he compound siiermary of Chara (fig. 313) consists of a splierical case comijosed of fmr triangular, plate-Uke cells ; from the inner face of eacli projects a handledike cell to whose end are attached 24 filaments, each composed of 100-200 disk-shaped cells. I'^ach of these con-. Fig. 312.âDevelopment of a sperm of a liverwort {PcIUa e/>i/'hyila\. n, mother cell with nucleus, the latter ajDproaching the wall; /â to //, nucleus elongating and curving into an arc, and finally a spiral coil ; r, an edge view, showing origin of cilia from periplieral iirotoplasm ; /, also an edge view ; /-, mature s[)erm, free. Magnified looo diam.âAfter Guignard. tains a sperm; so that each sperniar}' i)Tothices 20,000- 40,000 sperms. 384. Mossworts and fernworts. âIn the mossworts the spermar\- is a stalked body, \A'liose internal cells are the si)erm motlier cells, the outer layer fornung the spermar)^ wall (fig. 311)- In the fernworts the s])ermary is sessile and tlie number of mother cells is much smaller (fig. 314), corresponding lo the reduction in size of the gametoph\te (see ⢠395). \\'hcn the gauietoph\'te is greatly reduced, as iu the thih-uiosscs, a single spcrmarv only is formed, winch is e\cn larger than the I'cst of the gametophvte (fig. 315). 385. Seed plants. â In the seed plants the male ganieto- phyte begins to be formed before tlie nu"crosporc lea\es the sporangiimi. In gymuospcrms the spcu'c di\ides into two to cells, one or two of \\'liich reiiresent the \i'gctati\'e part. 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 Barnes, Charles Reid, 1858-1910. New York, H
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