1894. NEUTER INSECTS AND DARWINISM. 287 



Anyone who candidly and thoughtfully considers the views 1 

 have tried to express will see that Mr. Piatt Ball's objections are 

 superficial difficulties due to zeal for the dogma of natural selection. 

 In science everyone should take as his watchword surtout point de zele. 

 It is true we cannot maintain that the honey-pot modification in ants 

 was originally possessed by perfect males and females. But why 

 should we believe that the peculiarity is inherited at all ? There is 

 nothing unusual in ants or bees regurgitating honey, feeding one 

 another or larvae. A differentiation of habits must ensue when a 

 number of neuter insects live together in a community, simply 

 because all the individuals cannot be similarly related to their con- 

 ditions and their work. Mutual relations are established between 

 them, and those persons which remain in the nest, receive food, and 

 give it back again, may well, when food is plentiful, become distended. 

 The fact that one of these honey ants lives in Mexico and one in 

 Australia shows that the peculiarity has arisen twice independently. 

 It is not yet perfectly certain that the persons with the distended 

 abdomens are a separate caste : every individual may be at times in 

 this condition. 



Mr. Ball's statement of the case of the termites turns out to be 

 a characteristic anachronism. Like a good many other faithful 

 adherents of the theory of natural selection, he seems to have neglected 

 to take advantage of sources of information more recent in date than 

 the " Origin of Species." Not having made a special study of poly- 

 morphic insects, I found it difficult to obtain original papers containing 

 the results of research on these social neuroptera. I had a strong 

 conviction that when the subject was properly investigated it would 

 be found that the different castes were reared under different con- 

 ditions. At last I find that, according to Emery (4) the investigation 

 has recently been carried out, with the results which I anticipated. 

 Grassi, an Italian biologist, has satisfied himself and published direct 

 evidence that the termites have the power of regulating the number 

 of workers and soldiers by rearing them at will by appropriate feeding 

 and treatment, as they also hasten the sexual maturity of other indi- 

 viduals by special nourishment, and so produce the supplementary 

 sexual individuals which were so long a mystery. Emery concludes 

 that the workers of all social insects are reared in a similar way from 

 germs which are capable of producing normal sexual individuals. 



Mr. Ball's last objection as to the evolution of sterility in 

 neuters is a mere bladder which scarcely needs special pricking. It 

 has been disposed of by the general position taken up by Spencer 

 and myself. The only reasonable view is that the sterility of workers 

 is the necessary result of the habit of the ancestral insect to bestow 

 maternal care on her young. Is it not a fact that in the human 

 species the eldest sister in a large and struggling family has her 

 chance of marriage reduced ? The characteristics and the usefulness 

 of old maids in the human species are familiar enough ; does anyone 



