ZYGOPHYTA. 117 
and divides itself into sixteen cells, which then constitute 
anew colony similar to that with which we started (A, 
Fig. 50). 
243, The Water-Net (Hydrodictyon) is one of the most 
curious of the common plants of pools and slow streams in 
midsummer. Well-grown specimens are from 20 to 30 
centimetres long (8-12 inches), and consist of an actual net 
made of cylindrical cells joined at their ends. The whole 
Fia. 50.—A, a colony of Pandorina morum; C, sexual cells escaping; EZ, F, G, 
union of sexual cells; H, resting spore. All highly magnified. 
net is a colony, and the general mode of reproduction re- 
sembles that of Pandorina. 
244, New colonies are formed also directly by the proto- 
plasm of a cell first breaking up into a great number of 
‘small ones (by internal cell-formation), and then these soon 
arrange themselves into a miniature net inside of the old 
cell-wall. The old wall eventually decays and sets free the 
new colony. 
245. In the common Water-Flannel (Cladophora) of our 
