FKiHTING CONTKOLLKl) 97 



which is conditioned by the presence !' a female, 

 and that consequently when the male passes the 

 boundary, the impulse to return asserts itself and 

 the conflict ceases ; or we can say that the 

 occupation of a territory is the condition under 

 which the pugnacious instinct is rendered sus- 

 ceptible to stimulation, that the stimulus is 

 supplied by the intruder, and that when the male 

 passes outside the accustomed area its instinct is 

 no longer so susceptible and it therefore retires 

 from the conflict. 



Of these explanations, the first is not alto- 

 gether satisfactory. It requires the presence of 

 a female and, as we have seen, a female is by 

 no means always present. Then it attributes to 

 the one side of the inherited nature an influence 

 which is not borne out by the facts, for in the 

 ordinary routine of existence, without the incen- 

 tive of battle, every individual is liable to wander 

 occasionally beyond its boundary and to intrude 

 temporarily upon its neighbours ; and this it 

 could scarcely do, providing its nature to remain 

 within the territory were powerful enough to 

 dominate its movements and curtail its activities 

 even during the excitement of an encounter. 

 But there is nothing inherently improbable in 

 the alternative hypothesis, nor anything that 

 is at all inconsistent with the behaviour as 

 observed ; on the contrary, if it is admitted, the 

 facts become connected together and exhibit a 

 meaning which they otherwise would not have 

 possessed. 



So much for the controlling influence of 



