34 MINUTE MARVELS OF NATURE 



The envelope or cell-wall which surrounds each 

 granule shows clearly a double outline and con- 

 tains the life-matter known as protoplasm. Em- 

 bedded in this can be detected the living life 

 centre of each cell or plant, which botanists 

 term the nucleus. Each of these minute atoms 

 of plant life quickly attains to independent ma- 

 turity, and divides itself by means of a partition- 

 wall which forms like a film of ice and cuts the 

 cell into halves. Each half, when completely 

 separated, very soon divides again ; and so 

 myriads of plants are quickly formed, which 

 cover large areas in short spaces of time. 



In the Arctic regions early explorers were 

 astounded to find large areas of red snow ; but 

 the phenomenon is now familiar to men of science, 

 who know that^redsnow^ like a green garden 

 fence, is due to the presence of unicellular algae, 

 the only difference being in the colouring-matter 

 of the protoplasm. It is said that acres of snow 

 are frequently covered in a single night by these 

 tiny plants. 



Many vegetable cells are so small that over one 

 hundred millions would barely occupy a cubic 

 inch of space ; and in each of these the work of 

 life goes on. It is not necessary, however, to 

 examine these exceedingly tiny plants in order 

 to find single cells ; nor do they, perhaps, throw 



