148 ANIMAL INSTINCTS. 



tive or negative, which admit of being reached, A 

 larger design would needfully embrace vegetable in- 

 stincts also, from their close connexion and continuity 

 with those of animal life, but to these I can only here 

 cursorily refer. 



The question what we are to describe as instincts 

 first presses upon us one not easy to answer. We 

 can define them under their more special forms, as dis- 

 tinct from reason, and often even in direct conflict with 

 it. Such definitions are familiar ; based on endless in- 

 stances and satisfying the mind by their seeming com- 

 pleteness. Yet if we approach the phenomena more 

 closely, we find a border-land where reason and instinct 

 are strangely and inextricably blended each invading 

 the domain of the other, and reciprocally producing 

 changes which variously affect the functions of both. 

 Acts, primarily of reason and volition, pass by constant 

 repetition into habits having the compulsory force of 

 instincts, and often even transmissible to offspring ; 

 while instincts submitted to the pressure of unwonted 

 conditions often assume new faculties and modes of 

 action, which if we shrink from calling them acts of 

 reason can only be interpreted as newly- developed 

 forms of instinct. 



It is on this border-land, however, if anywhere, 

 that we may hope to obtain some enlargement and 

 better definition of our knowledge. Little or nothing 

 is gained by multiplying examples of individual in- 

 stincts, strange and curious though they be, and worthy 

 of a better classification than any yet adopted. Those 

 of the bee, the ant, the spider, the carrier-pigeon, the 



