158 The Study of Animal Life PART n 



mine the presence of perceptual inference than the absence 

 of consciousness ; this criterion may be of theoretical 

 interest, it is of no practical use. The other attributes he 

 enumerates should be carefully studied. 



Prof. Lloyd Morgan also separates, but by no hard-and- 

 fast line, the automatic and reflex actions, which are 

 reactions to definite stimuli, from instinctive actions, which, 

 according to him, are " sequences of co-ordinated activities, 

 performed by the individual in common with all the mem- 

 bers of the same more or less restricted group, in adaptation 

 to certain circumstances, oft recurring or essential to the 

 continuance of the species." 



He separates these from intelligent actions, which are 

 "performed in special adaptation to special circumstances." 



Instinctive activities he conceives to be performed 

 " without learning or practice." If the actions need a little 

 practice he calls them " incomplete instincts" ; if a great deal 

 of practice be necessary they are called " habitual activities" ; 

 if they are not perfectly developed at birth but after further 

 development can be performed without practice they may be 

 called " deferred instincts." A further useful classification 

 of instincts is into "perfect" and "imperfect," according to 

 the precision of their adaptation to the desired end. 



Mr. Lloyd Morgan's definition, like the others, implies that 

 one can separate rational from non-rational actions ; but he 

 safeguards himself by defining instincts as " oft-recurring or 

 essential to the continuance of the species," in contra- 

 distinction to intelligent actions which are performed in 

 special adaptation to special circumstances. It is important 

 to notice that the terms of the definition are that instincts 

 are either oft-recurring or essential, and not oft-recurring 

 and essential, for many instincts are only either one or the 

 other and not both. But it is not always possible to say of 

 a certain action that it is a special adaptation to a special 

 circumstance, and is therefore rational, and not in reality 

 an instinctive adaptation to circumstances that are of frequent 

 occurrence although we have not observed them to be so. 



This definition, however, emphasises the fact that instincts 

 are common to species ; it is, however, not easy to estimate 



