Our British Snails 27 



rats, rabbits, ducks, thrushes, and beetles) ; 

 but when kept and protected for observation 

 they have achieved the great age of even ten 

 years. 



They have a great power of " homing " like 

 pigeons, however far (for them) is their journey 

 after favourite food. The slime-marked journeys 

 or feeding tracks of this species (and still more 

 of slugs) afford matter of great interest. As 

 to sight the two eyes are the dark specks on 

 the tip of the upper pair of " horns,'' but the 

 range of vision is very short indeed, and the 

 difference between light and approaching dark- 

 ness is all that some seem able to perceive. The 

 organs of hearing are two small sacs filled with 

 fluid in which are some calcareous grains. They 

 hear little which is audible to human ears, and 

 if not altogether deaf they are dumb as far as 

 we can hear. The power of taste they possess, 

 as is shown by the preference of some foods to 

 others. The sense of touch is acute and resides 

 in all parts of the soft and moist external skin, 

 and especially in the upper tentacles or horns in 

 the HelicidcB. Jaws they have with which to 

 seize and to bite off food, and in H. aspersa and 

 others these bear teeth, but the chief work is 

 done by a sort of toothed tongue, the radula, 

 which rasps off particles of food with a side to side 

 motion of the head as the animal advances. 

 Our aspersa has 12,615 teeth on this ribbon, 



