lO Auditory Apertures in Quadrupeds and Birds, 



as excellent media for collecting sounds, and transmitting 

 them, through the bony portion of the canal, to the internal 

 ear. That these organs are valuable adjuvants to another 

 sense (that of sight) no one will doubt, especially when he 

 recollects that animals of this class, although possessing a 

 very wide expanse of sight, yet do not enjoy an equally dis- 

 tant one ; which is not to be wondered at, when we look 

 at the diminutive stature they exhibit : yet for this loss they 

 are compensated, by having the sense of hearing very acute 

 from a number of points, though much more from behind 

 than in any other direction. Many persons contend that 

 the hare cannot distinguish sounds immediately before her, 

 which is not unlikely when we consider the bony structure of 

 the external ear ; however, this is not absolutely necessary, as 

 her prominent eyes scarcely allow any object to approach her 

 without some part of its shadow being depicted upon the retina, 

 and thus communicatino: the alarm to the timid animal. 



As a contrast to the situation of the auditory tube in the 

 hare, I shall now mention that of the polecat {Jig. 4.); 



which animal is, as is 

 well known, a pursuing 

 one : consequently re- 

 quiring its external 

 senses, or rather the 

 communications for con- 

 veying impressions, to 

 them as forward as pos- 

 sible. This animal has 

 its external auditory 

 tube similar in length and diameter to the hare's ; placed at an 

 angle of 45^ (a), but pointing from behind, in a direction 

 downwards and forwards ; in fact, the very opposite to the 

 position described in the hare. When we consider the habits 

 of this animal, and behold the structure containing one sense 

 acting in concert with and supporting another still more valu- 

 able to the animal's existence, we cannot but wonder at the 

 excellence of arrangements that provides for wants which 

 mere human ingenuity can only comprehend, but could never 

 supply. 



From this tube being placed very forward, we should natu- 

 rally conclude that this animal's sense of hearing is necessa- 

 rily much less acute from behind than before : this supposition 

 I am inclined strongly to support, from the following circum- 

 stance : — A farmer in the neighbourhood had his poultry 

 disturbed on several successive niirhts, but could not make 

 out the cause ; till one day he discovered, near his residence. 



