, ‘ 4 \ ' % | ioe - 
- ‘ps aie 4 “* = ot ‘ % ; , i 4 , ) 
* Rie ~ a i ‘ / ( 4 & } 
af Vie { » i 5 Soh” 
4 % / 
y ’ The Cell as an Tndividnal. e 33 “ei é Ze 
- course of development two opposite conditions occur, which 
are distinguished as free cell-formation, and cell-division. 
In free cell-formation the masses of protoplasm of the 
mother-cell collect around the nuclei previously produced, 
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2 
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Fic. 55 I1.—Cell-division in the endosperm of the scarlet-runner seed. The 
cells which originated by free cell-formation have closed up, and now 9 
- multiply by division ; @ mother cell in its unchanged state ; 6 commence- : : 
ment, c completion of division into daughter-cells ;d a similar celltod,the: ~ 
contents of which have been contracted by the addition of water. (x 670.) 
and thus form themselves into new cells which remain en- cate 
closed within the mother.cell, the life of which still con- Jog 
tinues fora time. In most cases they have already formed a 
cell-wall of cellulose while still enclosed within the mother- 
cell, as in the case of pollen-grains and the embryo-sac of 
Phanerogams (Fig. 55 IJ.); less often not till after their 
escape, aS occurs in swarmspores. This membrane of . 
D | 
