8 



Habit and Instinct. 



affecting the whole behaviour of the organism, and there 

 seem to be internal promptings of some kind due to organic 

 conditions whose seat is within the body of the developing 

 larva. Or take the migration of birds, their nest-building 

 instincts, the activities involved in incubation and in 

 the rearing of their young ; there is surely, it may be 

 said, something in all this which may be distinguished, 

 even if the line of demarcation be hard to draw, from reflex 

 action. We cannot say more, however, than that the one 

 is a more fully corporate act than the other. 



Eeflex action is involved in the carrying out of many 

 instinctive activities. When the great water-beetle weaves 

 with her spinnerets the delicate silken cocoon in which 

 she deposits her eggs, there are reflex acts connected with 

 the extrusion of the fluid which hardens to form the silk ; 

 reflex acts accompany the moulding of the cocoon and its 

 being supplied with air ; reflex acts are concerned in the 

 laying of her eggs, " not at hazard, but in regular order, 

 side by side ; " but during the hours of maternal labour 

 there is an organization of all the activities into a definite 

 line of behaviour, directed to what we see to be a final and 

 adaptive end, and prompted, we feel sure, by some internal 

 impulse ; and all this tends to raise series of activities, as 

 a whole, above the level of mere reflex action. If we say 

 that reflex acts are local responses due to specialized stimuli, 

 while instinctive activities are matters of general behaviour, 

 usually involving a larger measure of central (as opposed 

 to merely local or ganglionic) co-ordination, and due to 

 the more widely spread effects of stimuli in which both 

 external and internal factors co-operate, we shall probably 

 get as near as possible to the distinction of which we are in 

 search. But it must be remembered that there are border- 

 land cases in which the distinction can hardly be maintained. 



Eeverting now to the close connection we have seen to 



