56 LLOYD'S NATURAL HISTORY. 



are three pairs of incisors, one of canines, three of pre-molars, 

 and three of molars. In the lower jaw, while the number of 

 canines and molars is the same, there are but two pairs 

 both of incisors and pre-molars. In the upper jaw, the inner 

 pair of incisors are conical and vertically-placed teeth, widely 

 separated from one another in the middle line, while the 

 lower incisors incline almost horizontally forwards. 



The spines clothing the bodies and sides of the Hedge-hogs, 

 which are generally marked with fine longitudinal grooves, are 

 inserted in a layer of tissue beneath the skin by small knob-like 

 terminations resembling pins' heads, and may thus be likened 

 to pins stuck through a piece of soft leather. Beneath the skin 

 lies a thick layer of muscle the panniculus carnosus which 

 is much more developed than in any other Mammal, and by 

 its contraction enables the creatures to roll themselves up into 

 the well-known ball-like form, when the head and limbs are 

 completely concealed from view, and only a uniformly formid- 

 able array of radiating spines exposed. 



Hedge-hogs are exclusively Old World animals, and are 

 distributed over the main portion of the three great continents, 

 although they are unknown in Madagascar, Ceylon, Burma, 

 and the Malayan region. As a rule, the numerous species are 

 exceedingly like one another, both as regards external appear- 

 ance and their general structure, although, somewhat curiously, 

 ths European species differs in certain respects from the whole 

 of the rest. 



I. THE COMMON HEDGE-HOG. ERINACEUS EUROPCEUS. 



Erinaceus suropxus^ Linn., Syst. Nat- ed. 12 vol. i. p. 75 

 (1766); Bell, British Quadrupeds 2nd ed. p. 102 (1874). 



(Plate V.) 



Characters. Both the third upper incisor and the canine in- 

 serted by single roots; the fur usually long and coarse. 



