THE HEDGE-HOGS. 55 



already mentioned, belong to the group characterised by the 

 W-like arrangement of the cusps of the upper molar teeth, are 

 classified under three families, of which the first is 



THE HEDGE-HOGS AND THEIR ALLIES. FAMILY 

 ERINACEID^. 



Although the well-known spiny covering of the Hedge-hogs 

 would, by non-zoological readers, be regarded as the most 

 characteristic feature of the Family to which these creatures 

 belong, yet, as a matter of fact, it is of no real importance. 

 Thus, for instance, while similar spines occur in the Tenrecs of 

 Madagascar, which belong to another family of the Order (per- 

 taining to the group with a V-Iike arrangement of the cusps on 

 the upper molars), in the so called " Gymnuras " of the Oriental 

 region, which are included in the present Family, such spines 

 are totally wanting. Under these circumstances naturalists 

 have to resort to other characters by which to define the 

 Family. Since, however, these are somewhat technical, and 

 require a certain amount of anatomical knowledge for their 

 proper comprehension, we shall not allude to them here, as it 

 is sufficient for the purposes of this work to state that in 

 Britain the Family is represented solely by the Hedge-hog, 

 which cannot possibly be confounded with any other of our 

 native animals. 



THE HEDGE-HOGS. GENUS ERINACEUS. 

 Erinaceus, Linn., Syst. Nat. ed. 12 vol. i. p. 75 (1766). 



The genus may be shortly defined as including those mem- 

 bers of the family in which the back and sides are covered with 

 short spines, and the tail is short and rudimentary. 



Hedge-hogs have a total of thirty-six teeth, there being ten 

 pairs in the upper and eight in the lower jaw. Of these, there 



