HEARING — GENERAL 75 



the Wood Mouse and Brown Rat, the outer ear is normally 

 held flat against its head and has not got the trumpet shape 

 which is so clearly seen in the other two species referred to. 

 Whether mice and rats can hear fainter sounds than water 

 voles it is difficult to say, and it would be a most interesting 

 experiment to carry out tests designed to show their relative 

 acuteness of hearing. 



Deer of all kinds, in my opinion, have hearing which is 

 equal to their sense of smell ; and a hunted deer, while using 

 its nose to obtain the maximum amount of protection from 

 and warning of danger, will use its hearing for the same 

 purpose with great advantage. It can discriminate between 

 the baying of hounds and the barking of farm dogs (of which 

 it will take no notice) over considerable distances ; and when 

 the wind is unfavourable for scenting purposes, I believe that 

 deer rely mainly on their hearing. 



Hares and foxes, too, use their ears to a great extent, while 

 badgers have a most delicate sense of hearing, as anyone 

 who has tried their novice hand at badger-watching will soon 

 learn. 



The peak of hearing ability in mammals is reached by the 

 bats which, as is now fairly generally known, navigate and 

 even locate food by means of their specially adapted auditory 

 mechanisms. The basis of this super-normal sensitivity lies in 

 their ability to utter high-pitched squeaks which, when as 

 sound waves they bounce back towards the bat, can be used 

 and interpreted to tell the bat how far away is the object 

 from which the squeaks have returned as echoes. 



While it is always difficult to compare the degree to which 

 an animal uses one sense or another, it is safe to say that the 

 majority of animals utilize their acuteness of hearing far 

 more than the average person thinks. 



