130 



INSKCTIVOEA 



ERINACEUS ALGIRUS Duveriioy and Lereboullet. 



(Synonymy under subspecies.) 



GeograpMcal distribution. — Northern Africa ; also in southern 

 Spain, southern France, and the Balearic Islands. 



Diac/nosis. — Smaller than Erinaceus europseus (hind foot less 

 than 40 mm.) ; sjDines not so coarse ; middle of forehead with 

 bare area among the spines : skull with sagittal crest extending 

 forward to middle of frontal ; a wide flattened area on each side 

 of bony palate behind transverse ridge ; third upper incisor with 

 two perfectly distinct roots ; elevated portion of posterior lower 

 premolar with only two cusps (fig. 2b b). 



External characters. — Externally Erinaceus alyiriis is dis- 

 tinguishable from E. europseus by its smaller size, shorter, more 

 slender and apparently more densely-set bristles, and by the bare 

 area at middle of forehead. This bare area is about 7 mm. wide 

 and extends back about 10 to 15 mm. from front line of spines. 

 In dried skins it is sometimes partly hidden by shrinking. Fur 

 more dense and less coarse than in the larger animal. Claws on 

 front feet seldom attaining a length of 8 mm. 



Coloxir.- — The colour resembles in general that of the paler 

 races of E. euroj.seus. 



SlxulL- — The form of the skull is essentially as in E. < uropseus 

 except that rostrum is less elevated posteriorly, so that the dorsal 

 profile tends to become slightly concave. Sagittal crest when 

 fully developed extending forward to middle of frontal, while in 

 E. europseus it is visually confined to parietals, rarely encroaching 

 on posterior edge of frontal. Ridge at margin of orbit very short, 

 scarcely more than a process above lachrymal foramen. Bony 

 palate extending behind transverse ridge as a well-defined flat area 

 divided along median suture by a longitudinal ridge representing 

 the median spine of E. europseus. Basisphenoid pit narrower, 

 relatively deeper, and with more overhanging edges than in 

 E. europseus. 



Teeth. — In general the teeth show no departure from those 

 of E. europseus. The posterior lower pre- 

 molar, however, lacks all trace of the meta- 

 conid, so that the resemblance of the elevated 

 portion of the tooth to the first triangle lof 

 wtj and m.^ is completely destroyed. In the 

 upper jaw the third incisor, canine, and 

 a h first premolar are two-rooted, apparently 



Fig. 2.5. without exception. 



Large lower premolar of Measurements. — Head and body about 



and'^.''aJ^(>Ms°(iO.''*x3*. 200 to 250 ; tail, 25 to 40 ; hind foot, 32 to 

 37 ; condylobasal length of skull, 54 to 59 mm. 

 Memarhs. — Thisspecies is readily distinguishable fromJG/•/J^ace^^s 

 europseus by the bare spot among spines of forehead, the perfectly 

 two-cusped large lower premolar, and the two-rooted third upper 



