TAXONOMY 



237 



ments arrange themselves side by side, and the cells lying opposite 

 each other undergo internal changes so as to form gametes or sexual 

 cells. Each protrudes a process or conjugation tube; these unite 



FIG. 114. Spitogyra sp. A, terminal portion of vegetative filament; B, stages 

 of scalariform conjugation; C, preparation for lateral conjugation; D, zygospores 

 formed by lateral conjugation. (Gager.) 



and the protoplasm from one cell passes over and coalesces with that 

 in the cell opposite. The result of the process is a new cell called a 

 zygospore or zygote. This is set free by decay of the walls of the old 



