HEARING — FIELDWORK AND EXPERIMENTS 85 



course, present in cats of all kinds, but it cannot be too 

 strongly stressed that even the best endowed mammal is, in 

 this respect, at a disadvantage under conditions of pitch 

 darkness. An additional sense to aid in catching live food is 

 clearly necessary, and hearing is what assists a cat to locate 

 victims at some distance, after which its stealthy movements 

 will bring it close enough for a catch to be made. 



It is scarcely necessary to suggest special tests in order to 

 prove the delicacy of hearing in the feline family nor, indeed, 

 is much more required for dogs in the same context. How- 

 ever, there are two points worth mentioning. The first is 

 the use of so-called "silent dog-whistles". These are whistles 

 in which the construction is such that no noise audible to 

 us is produced. Dogs can easily and quickly be trained to 

 respond to the very high-pitch vibrations of these whistles, 

 and this ready response is surely proof enough of their 

 ability to hear very high frequencies. 



The second point is in connection with the limitations as 

 regards the location of sounds in dogs, and to some degree 

 in cats too. Dogs will seldom be able to locate a sound which 

 comes from a point well above them ; and this can be shown 

 by calling or whistling a dog from some elevated position — 

 an upstairs window or some similar spot. A dog will hear the 

 sound all right, but will not be able to tell from which 

 quarter it originates. 



Deer are endowed with an acute sense of hearing ; and 

 those who live in districts where our Red, Roe, and Fallow 

 Deer — particularly the two former species — are to be found 

 should have no difficulty in proving to themselves the value 

 of good hearing to deer as a means of escaping danger. Any 

 deer-watcher, stalker or hunter knows that as much caution 

 must be observed in respect of quiet and careful movements 

 as in respect of the necessity to keep down wind of these 

 animals and so avoid being scented by them. 



Horses, cattle, sheep, hares and rabbits (where the latter 

 still exist) all offer opportunities for observations on their 

 hearing abilities. No student of badger or fox life will be 

 successful if, having established himself at a "set" or "earth" 

 for the purpose of keeping watch, he moves about or allows 

 his clothing to brush against bushes and undergrowth; he 



