376 BOTANY OF THE LIVING PLANT 



Such suggestions as these are based upon the actual facts observed 

 in simple organisms referable to the Flagellatae, It may be uncertain 

 whether or no these forms were or were not like the original 

 sources from which Vegetable and Animal Life sprang. They serve 

 however, to give some idea of the possible origin and early relations 

 of the larger groups of living organisms, and of their differentiation 

 on the basis of nutrition, and of certain fundamental features of their 

 structure. In point of habitat the significance of these comparisons 

 cannot be mistaken ; for all these organisms are either aquatic, or at 

 least they live where water is readily available. 



