ANIMAL INSTINCTS. 161 



parative observation and on experiment, is still want- 

 ing to us. More hands than one might be required, 

 but it is a work which would well repay in probable 

 results any amount of labour bestowed upon it ; having 

 peculiar interest, moreover, in its connexion with the 

 question of the origin of species, to which I have 

 already alluded. The main problem to be solved is 

 the relation, as to priority or causality, between the 

 organisation and the instincts of species. To this must 

 be added subordinately all that concerns the hereditary 

 nature of instincts their relation to habits and casual 

 conditions of life, including here the divergence of spe- 

 cies into races, and the influence upon them of reason 

 and the will. The doctrine of transmutation or evolu- 

 tion, refusing to admit the special creation of new 

 forms of animal life, can only explain the diversity of 

 instincts by supposing changes of organism, needfully 

 involving changes of the instinctive functions ; and this 

 not only where reason and instincts work together, but 

 also in those cases, far more numerous, where the 

 latter, wholly detached from intelligence, are altogether 

 compulsory in their nature. I have already given the 

 reasons which seem to me to make it certain that in- 

 stincts cannot belong to structure only. In a matter 

 thus obscure, where an unknown power comes into the 

 question, it is something to obtain even such negative 

 conclusion. If we. ever reach one more positive, it 

 will probably be on that border-land already denoted, 

 where mental and material functions, intelligence and 

 instincts, are found together either in co-operation or 

 conflict. 



