PROTOPHYTES. 41 



two Greek words : protos, first, and coccus, a berry. 

 Each cell is round, and varies in color from bright 

 green to bright red, according to the nature of the 

 coloring matter diffused in the form of granules 

 through the bioplasm. It requires a microscope to 

 see the form and structure of these cells. Each cell 

 is a perfect plant, and like all vegetables which con- 

 tain chlorophyll, (Chap. V, Sec. 9,) under the influence 

 of sunlight, breaks up the carbonic acid gas which it 

 absorbs from the air, retaining the carbon and giving 

 off the oxygen. In the dark, however, all plants ab- 

 sorb oxygen arid give off carbonic acid, rendering it 

 unsafe to have many plants in a sleeping-room, since 

 carbonic acid gas is unfit for respiration by men and 

 animals. 



The cell-wall of the protococcus is quite transpar- 

 ent, and if burst will allow the bioplasm and the 

 granules of red or green chlorophyll to escape. The 

 cells multiply by self-division, each one producing 

 two, four, eight, or sixteen cells. These new cells 

 differ from the parent cell in not remaining quiet or 

 still, but having the power of active movement. 

 They swim about like animals by means of two fila- 

 ments or cilia, (Lat. cilium, an eyelash.) These 

 moving cells may also subdivide into smaller ones 

 which have been called by botanists zoospvres, (Gr. 

 zoos, life, and sporon, seed,) or living seeds. Many 

 of the moving cells, however, lose their cilia and 



