132 BOMB COMMON MAMMALS. 



We also notice, as we turn over the fur, that it does not 

 possess the property known as " set." That is, it stands 

 almost straight out from the body, and brushes readily in 

 any direction. It is not difficult to understand the mean- 

 ing of this in a creature moving constantly in a narrow 



burrow. A " set " to 

 the fur would be al- 

 together unnecessary. 

 The structure of a 

 mole's hair is unusual 

 (Fig. 41). 



The cylindrical body 

 has deprived the crea- 



Fig. 41. Hairs of Mole, showing the regular i - , ' -t , 



variations in thickness. A magnified por- head tapers almost 



tion of a hair is shown below. suddenly in front of 



the body; it exhibits 



several peculiarities of interest. The snout, tapering down- 

 ward at the tip, is long. Within there is an extra bone 

 strengthening it, as it assists the claws in pushing the 

 earth aside. The mouth below is suitably some distance 

 behind the tip. It is like a long narrow JJ, the margins 

 are thin, and that of the upper jaw forms a close covering 

 to the teeth, an effective curtain shutting out grit. 



The teeth are sharply pointed, the canines in particular 

 are long and sharp, and well adapted to dealing with the 

 wriggling earthworm upon which the mole feeds. The 

 tongue is long and narrow like a strap, very useful also 

 we imagine in dealing with the earthworms. Around the 

 snout there are numerous sensory bristles, both above and 

 below. All these things should be pointed out to the 

 pupils. 



Our next interesting quest is for the mole's eyes. By 

 blowing aside the fur, we disclose the tiny jet-black eyes. 

 The mole is not blind, though its vision is blurred. It can 

 see moving objects, if it does not see them clearly. The 

 mole depends on its other senses more than upon its eyes. 



The ears are without an external lobe, and, further, are 

 situated at the end of quite a long narrow tube. By blow- 

 ing aside the fur which conceals it, this tube may be seen. 



