The Mole. 



309 



directed outwards ; the hand is susceptible of being only 

 partially closed, which is effected by the inclination of the 

 terminal joint above. When thus bent the hand is formed of 

 two portions ; the one consisting of the palm turned outwards, 

 and the other formed of the terminal joint at the digits, the 

 direction of which is backwards, a structure which readily 

 explains the mode in which the soil is shovelled away and 

 flung backwards behind the animal when at work. 



Keenness of sight not being required in the darkness of its 

 underground chambers, that sense is reduced to a minimum 

 of development, but contrary to popular belief the animal is 

 not blind, although the eyes are very minute and completely 

 buried in the fur which surrounds them. A German naturalist, 

 Carl Hess, has proved by minute microscopical examination 

 that the eye of the Mole is perfectly capable of seeing, and, in 

 spite of its minute dimensions (i mm. by 0*9 mm.) it possesses 

 all the necessary properties for seeing that the most highly 

 developed eye does ; that it is, in fact, as well suited for 

 seeing as the eye of any other mammal, and that in the matter 

 of refraction it does not differ from the normal eye. 



In order to bear out the theory of shortsightedness, 

 the physiological reason was adduced that in its sub- 

 terranean runs the Mole is accustomei to see things at short 

 distances, and that its eye had become gradually suited 

 to near objects. But to this, Herr Hess objects that the Mole 

 when underground most probably makes no use of its eyes at 

 all, as it would be impossible to see anything owing to the 

 absence of light ; but that when it comes to the surface, and 

 especially when swimming, it does use its eyes. In order to 

 accomplish this, it has only to alter the erect position of the 

 hairs which surround and cover the eyes, and which prevent 

 the entry of dirt when underground, and at the same time to 

 protrude the eyes forward. 



The sense of smell in the Mole is believed to be well 

 developed to enable the detection of its prey, its enemies, 

 and its own kind. The sense of hearing, also, is very keen. 

 It will take alarm at the slightest sound, and will not come 

 forth until all is still again. This has been proved by 



