130 ANIMAL INDIVIDUALITY [CH. 



continued existence. If the moth had not the struc- 

 ture to form the pollen-ball and the instinct to put it 

 on the stigma, the ovules would not be fertilized and 

 her offspring would have no food; and if the plant 

 was not prepared to sacrifice some 10 per cent, of its 

 brood, the rest would never develop at all. Here it 

 is of course the two species that are affected, while 

 the single moth and the single plant do not depend 

 on each other in any way ; but the essential point of 

 the relation the mutual helpfulness of two unrelated 

 kinds of protoplasm remains the same. 



Now return and consider these various relation- 

 ships from the point of view of individuality. The 

 different species of living things and their members 

 are all bound up, though but loosely, into a general 

 whole. Any single species relies on others for some 

 of the necessities of its existence. In many green 

 plants this dependence on other species is very slight 

 and very indirect, while animals, owing to their mode 

 of nutrition, are always directly dependent on the one 

 or many organisms on which they feed. None the 

 less, in nett total of true independence most animals 

 are far ahead of plants. They have had to make more 

 effort to get their food, and throughout life, effort 

 always seems to bring in its train advantages, unfore- 

 seen and unconnected with the effort's immediate 

 object. To give an extreme example, the eyes and 

 ears and other sense-organs of animals were developed 



