THE PRINCIPLE OF CO-OPERATION 353 



to laws, and these are the same everywhere that such facts appear, 

 so that they constitute a considerable and uniform domain in nature, 

 a homogenous whole thoroughly integrated in all its parts.'" 



More recently Kropotkin, Deegener, Alverdes, and Wheeler have 

 contributed to the development of this thesis. The latter, in Social 

 Life among Insects (1923) expressed his point of view as follows: 

 "All living things are genetically related as members of one great 

 family, one vast living symplasm, which though fragmented into 

 individuals in space, is nevertheless absolutely continuous in time. 

 In the great majority of organic forms each generation arises from 

 the co-operation of two individuals. Most animals and plants live 

 in associations, herds, colonies or societies and even the so-called 

 'soKtary' species are obligatory, more or less co-operative members 

 of groups or associations of individuals of different species. Living 

 beings not only struggle and compete with one another for food, 

 mates and safety, but they also work together to insure to one an- 

 other these same indispensable conditions for development and sur- 

 vival." 



We are not concerned here, as some recent writers have been 

 (Wheeler, 191 1, 1930; Child, 1924), with renewing the Spencerian 

 analogy between the living and the social "organism" however much 

 we are impressed by the remarkable similarities between the inter- 

 relations of the organelles of a cell or the organs of the body, and 

 the individuals composing a heteromorphic hydroid colony or a con- 

 sociation of free individuals. Rather, it has been our task to present 

 material gathered by numerous workers in the field of ecological 

 physiology, particularly that collected within the last decade, and 

 to focus it upon the present problem. The results obtained show 

 that the generahzations of Espinas, of Deegener, and of Wheeler 

 rest upon a broader base than that furnished by observational be- 

 havior studies concerned primarily with the struggle for existence 

 as conceived in the nineteenth century, and with the more obvious 

 survival values, or upon the lives of insects admittedly social in 

 habit. 



Certain of these problems with which we have been deaUng be- 



' Translated by Wheeler, 1928. 



