94 Darwin, and after Darwin. 



tion indicates — if it does not actually prove — that 

 they are descended from working insects which were 

 able to propagate. Thus, in all probability, what we 

 now call a "hive" was originally a society of sexually 

 mature insects, all presenting the same instincts, both 

 as to propagation and to co-operation. When these 

 instincts, thus common to all individuals composing 

 the hive, had been highly perfected, it became of 

 advantage in the struggle for existence (between 

 different hives or communities) that the functions 

 of reproduction should devolve more upon some 

 individuals, while those of co-operation should devolve 

 more upon others. Consequently, this division of 

 labour began, and gradually became complete, as 

 we now find it in bees and ants. Perrier sustains 

 the hypothesis thus briefly sketched by pointing 

 to certain species of social hymenoptera where 

 we may actually observe different stages of the 

 process — from cases where all the females of the 

 hive are at the same time workers and breeders, up 

 to the cases where the severance between these func- 

 tions has become complete. Therefore, it seems to 

 me, it is no Ioniser necessary to suppose that in these 

 latter cases all the instincts of the (now) barren females 

 can only have been due to the unaided influence of 

 natural selection. 



Nevertheless although I think that Perrier has 

 made good his position thus far, that his hypothesis 

 fails to account for some of the instincts which are 

 manifested by neuter insects, such as those which, so 

 far as I can see. mu.st necessarily be supposed to 

 have originated after the breeding and working 

 functions had become separated — seeing that they 



