5S FLOWERLESS PLANTS 



limited. Of course, where water is in swift 

 motion the amount of vegetable life is always 

 much less than is the case with lakes or slow- 

 moving rivers. 



In the case of a very large number of these 

 minute algae the process of reproduction is 

 comparativel}' simple, in that it chiefly consists 

 of a division of the cells. Increase by means of 

 small bodies known as zoospores is very common 

 in some orders. These are really tinj^ specks 

 of protoplasm — the life basis — which are re- 

 leased from the cell of the plant and move about 

 in the water by means of delicate cilia. After 

 awhile they come to rest, and are finally in- 

 vested with a cell wall, and in this way give 

 rise to a new individual. In some cases it is 

 to be observed that two masses of proto- 

 plasmic matter become joined together, and 

 so give rise to a new individual. The large 

 colony of cells which go to form the Volvox so 

 familiar to microscopists evinces the union of 

 sex elements. Within the hollow sphere (which 

 is continually being propelled about through 

 the agency of ciha which certain of the cells 

 thrust out) there are formed egg cells which are 

 fertihsed by the very active male bodies, the 



