Preliminary Definitions and Illustrations. 21 



be considered." With herons and rooks, the falcon is 

 generally kept hooded till the quarry is in sight, when 

 she is at once unhooded and slipped. With game birds the 

 falcon is taught to " wait on " tiU the game is flushed. 

 " A good game hawk in proper flying order goes up at once 

 to a good pitch in the air the higher she flies the better 

 and follows her master from field to field, always ready 

 for a stoop when the quarry is sprung. Hawks that have 

 been successfully broken and judiciously worked become 

 wonderfully clever, and soon learn to regulate their flight 

 by the movements of their master." 



These facts and extracts from Colonel Kadcliff's article 

 on " Falconry " * will serve to show how the behaviour of a 

 trained falcon is an adaptation and modification of the 

 hawk's congenital instincts as a bird of prey. The finished 

 performance is part instinct and part habit. The basis 

 is instinctive and congenital ; the modification is a matter 

 of acquired habit. In domesticated animals that are not 

 only reared, but also bred, by man, there is opportunity for 

 selective mating; and there is opened up the question 

 whether the acquired modification of instinctive behaviour 

 becomes congenital through heredity. Hence in the 

 training of a retriever there may be hereditary effects 

 which are absent in the case of the falcon. 



It may be objected, however, that the distinction be- 

 tween " congenital " and " acquired " is one that cannot 

 be sustained, since after all an organism can only acquire 

 that for acquiring which it inherits a potentiality; and 

 that we must in any case come back to heredity in the 

 last resort. The Scandinavian jer falcons (F. gyrfalco), for 

 example, will seldom "wait on "well; and merlins will 

 not do it at all. They inherit no faculty for responding to 

 training in this respect. Not only, therefore, is that which 



* " Encyclopaedia Britannica," 9th edit. vol. ix. 



