280 



PLAN 



T LIFE. 



but the seed plants was described in Part I. The forms of 

 the spermaries are as follows : 



383. Chara. The compound spermary of Chara (fig. 

 313) consists of a spherical case composed of four triangular, 

 plate-like cells ; from the inner face of each projects a 

 handle-like cell to whose end are attached 24 filaments, each 

 composed of 100-200 disk-shaped cells. Each of these con- 



FIG. 312. Development of a sperm of a liverwort (Pellia epiphylla\. a, mother cell 

 with nucleus, the latter approaching the wall ; l> to /i, nucleus elongating and curving 

 into an arc, and finally a spiral coil ; e, an edge view, showing origin of cilia from 

 peripheral protoplasm ; /, also an edge view ; k, mature sperm, free. Magnified 1000 

 diam. After Guignard. 



tains a sperm; so that each spermary produces 20,000- 

 40,000 sperms. 



384. Mossworts and fernworts. - -In the moss worts the 

 spermary is a stalked body, whose internal cells are the sperm 

 mother cells, the outer layer forming the spermary wall (fig. 



3 11 )- 



In the fernworts the spermary is sessile and the number of 

 mother cells is much smaller (fig. 314), corresponding to the 

 reduction in size of the gametophyte (see ^[ 395). When 

 the gametophyte is greatly reduced, as in the club-mosses, 

 a single spermary only is formed, which is even larger 

 than the rest of the gametophyte (fig. 315). 



385. Seed plants. In the seed plants the male gameto- 

 phyte begins to be formed before the microspore leaves the 

 sporangium. In gymnosperms the spore divides into two to 

 six cells, one or two of which represent the vegetative part 



