510 PATTEN— COOPERATION AS A FACTOR IN EVOLUTION. 



mands of a growing body, the conveyers must ultimately be utilized 

 to their full capacity ; when that point is approached, the rate of 

 growth will- diminish, for the expenditures for conveyance will tend 

 to exceed the creative value of the products. The previous rate of 

 growth can then only be maintained by economizing, or improving, 

 or by extending, the ways and means of conveyance. That is to 

 say, either the lines of conveyance must be lengthened, or the rate 

 of conveyance accelerated, or the powers of penetration increased. 



But better conveyance simply means better methods of coopera- 

 tion to that end between the older products of growth ; that is, it 

 means the using of those methods which yield more profitable ex- 

 change, or which create still more voluminous and diversified prod- 

 ucts. These new products then constitute the new means to a still 

 larger end ; for the creation of diversified products is essential to 

 the invention of new methods of organic cooperation. 



12. Growth, therefore, is automatically controlled. For since the 

 rate and the extent of growth depends on the capacity of its con- 

 veyers, growth will be checked whenever the new demands created 

 by growth approach the full capacity of its conveyers, and it will be 

 released when better ways and means of conveyance have been 

 found. Thus growth always tends to outrun cooperation, and better 

 cooperation always produces more growth, with new inperfections 

 which still better cooperation alone can remedy. 



13. The rate and direction of evolution varies greatly from time 

 to time, according to the methods of cooperation utilized. 



These changes of pace and direction in evolution are the real 

 basis of our systems of classifying the organic and inorganic prod- 

 ucts of nature. 



14. The principal kinds of conveyance in the internal organic 

 life of the individual are nervous, alimentary, vascular, and excre- 

 tory; in the external life they are cosmic circulation, locomotion, 

 and communication. All the epoch-making events in organic evolu- 

 tion are due to the introduction of better service in one or more of 

 these methods of conveyance. 



15. The changes of pace in organic evolution, following the adop- 

 tion of important improvements in cooperation, in retrospect appear 

 as gaps of larger or smaller magnitude, between classes, orders, and 



