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into two very unequal portions ; the smaller portion or “ basi- 
diospore ” becomes detached ; the larger portion remains 
behind, rapidly grows to its original size, and again and again 
repeats the same process. The process described in some text- 
books as the “ Gemmation ” or u Budding ” of cells, character- 
istic of the yeast-plant and other very lowly organised Fungi, 
Fig. 6. 
A 
A, B, C, a cylindrical cell of Spirogyra longata in successive stages 
of division ; B, E, the central portion of the same cell ; q, the 
new wall of cellulose in the process of formation. 
is a simple process of cell-division. The protoplasm-sac of the 
cell swells on one side, carrying the cell-wall along with it ; 
the papilla thus formed becomes subsequently separated by 
constriction, secreting an intermediate wall of cellulose, and 
ultimately becomes detached as an independent cell. 
It only remains to describe the mode in which cells develop 
into tissues. The simplest forms of vegetable life, as the 
Pcdmella cruenta and nivalis , or “ Red-snow,” among Algae, 
consist of single cells, which perform all the functions of life, 
both vegetative and reproductive. Others again, both Algae 
