THE HIGHER ORGANISMS 157 



greater number of living beings belong to the vegetable 

 kingdom, which has achieved its success entirely without 

 such aid. With immensely restricted powers of move- 

 ment, defenseless, as a rule, with no nervous system, no 

 sensory organs, no consciousness, by purely vegetative 

 development, through favorable accidents, multiplying 

 in vast numbers, dying in vast numbers, the chief sup- 

 port of the animal world which feeds upon them, these 

 organisms have covered the earth and filled the waters 

 in inconceivable numbers and endless variety. 



But, as has been said, the animal world developed 

 along different lines and almost immediately began to 

 profit by the constructive energy of the plants utilizing 

 their protoplasm to their own advantage, and appar- 

 ently finding it more easy to work with materials already 

 prepared than to manufacture for themselves. Thus, 

 animals became predatory and have continued to nourish 

 themselves exclusively at the expense of plants and each 

 other. 



To find food already prepared may require long 

 excursions, hence the animals, with few exceptions, 

 developed the power of locomotion. The food must be 

 found, must be caught, must be transformed, hence 

 in animals are found organs that would be as useless 

 as they are unknown to the plants. To find, to recognize, 

 to seize, to ingest, to digest, to circulate, to assimilate, 

 are all functions attended with more or less complexity 

 and for which special organs are indispensable. To 

 meet these requirements, organs of special sense appear, 

 though not in an order that makes their evolution 

 simple or easy to follow. It might be imagined that 

 the necessity for all of these desirable functions was 

 simultaneously experienced and that they began their 

 development about the same time, for one no sooner 

 finds himself well on his way to trace the beginnings of 

 the sense of touch, than he finds the foreshadowings of 

 the organs of vision and of other special senses. 



With this confusion of beginnings in mind, the follow- 



