( 325 



VAEIATIONS IN THE DENTITION OF ERINACEUS 



EUROPMUS. 



By Edwin Hollis, F.Z.S. 



My attention having been attracted to some curious variations 

 in the teeth of some Hedgehogs taken in the neighbourhood of 

 Exeter, I consulted several books, and found that they all give 

 as a characteristic the fact that E. europceus differs from the 

 other members of the Erinaceidce in having the third upper 

 incisors and canines single rooted, whereas in other species 

 these have two distinct roots. 



The following extracts (from ' Mammals Living and Extinct,' 

 Flower and Lydekker) bring out the above distinctions very 

 clearly. In writing of the Erinaceidce they say : — 



" The canine is very similar to the third incisor, and except 

 in E. europceus each of these teeth is inserted by two distinct 

 roots." 



" E. europceus is the most aberrant species, differing from all 

 the rest in the peculiarly shaped and single rooted third upper 

 incisor and canine." 



" The Indian form, E. collaris, may be considered character- 

 istic of all the other species, the only important differences being 

 found in the variable size and position of the second upper pre- 

 molar, which is very small, external and deciduous in E. micropus 

 and pictus." 



To emphasize the above points, they figure E. collaris (p. 620, 

 fig. 280) and E. europceus (p. 620, fig. 285), both after " Dobson, 

 Proc, Zool. Soc. Lond. 1881." 



The specimens I had under observation appeared to show 

 characters placing them midway between E. europceus and the 

 other species as above described. Thinking that this might 

 indicate that these were of a distinct local race peculiar to 

 Devonshire, I obtained further specimens from Sussex, North- 

 ampton, and Bucks, but found on examination that these pre- 

 sented the same peculiarities. 



I give below a table showing the peculiarities of eleven skulls 

 which I have now before me : — 



