INSECT-EATING MAMMALS. 45 



first and second upper molar teeth have five distinct cusps, the central one of 

 which is minute. and connected with the two inner ones by oblique ridges. 

 The family is confined to the Old World. 



The hedgehogs (Erinaceus) are sufficiently distinguished by the coat of 

 spines covering the upper surface and sides of the body, and their power of 

 rolling themselves up into a ball as a defence against attack, and are likewise 

 such familiar animals, that but little in the way of description is neces- 

 sary. The tail is extremely short ; and the total number of teeth is 36. 

 Hedgehogs are distributed over the greater part of Europe and portions of 

 Africa and Asia, although unknown in the countries lying east of the Bay of 

 Bengal, and likewise in Madagascar. The European species (E. europceus) 

 differs from all the others by the coarser nature of the fur between the spines, 

 and by the upper canine tooth being inserted by one instead of two roots. 

 In habits, all hedgehogs are nocturnal and omnivorous, their diet comprising 

 insects, molluscs, eggs, voles, fruits, and roots. In cold countries they hiber- 

 nate in a nest made of leaves and grass, and well concealed among bushes. 



The shrew-hedgehogs, which may be compared to large, coarsely-haired 

 shrews, replace the hedgehogs in Burma and the Malay countries. They 

 differ from the latter by being covered with 

 coarse hair instead of spines, as well as in 

 having 44 teeth. There are two species, 

 of which Raffles' s shrew-hedgehog (Gymnura, 

 rafflesi) is by far the commoner, and con- 

 siderably the larger, measuring 12 or 14 

 inches to the root of the tail, which is long 

 and rat-like. The smaller shrew-hedgehog 

 (Hylomys suillus\ on the other hand, measures 

 less than 5 inches, with a tail of only an inch 

 in length, and has the third upper premolar .-- 



tooth much smaller than in the first species. (Gymnura rafflesi). 



The range of both is nearly co-extensive. 



The numerous representatives of this extensive family are mouse-like or 

 rat-like creatures, with soft, short fur, long and pointed snouts, rounded 

 ears, closely pressed to the sides of the head, and a very 

 peculiar type of dentition. From ordinary rats and mice The Shrews. 

 they may be distinguished by their typically insectivorous Family 



snouts ; but it is remarkable that a peculiar rat recently dis- Soricidce. 

 covered in the Philippines is curiously like a shrew in this 

 respect, although it retains the characteristic rodent incisor teeth, which are, 

 however, reduced to an exceedingly small size. As regards their dentition, 

 shrews are specially characterised by the first pair of upper incisor teeth being 

 long and generally sickle-shaped, with a more or less distinct projecting basal 

 cusp on the hinder border, while those of the lower jaw are long, and projecting 

 forwards, in some cases with an upward curve at the tip. With the excep- 

 tion of one African species, there are only six pairs of lower teeth. A pecu- 

 liarity of the skull of the shrews is the absence of the bony zygomatic arch 

 running beneath the socket of the eye, although the same deficiency is found 

 in one species of hedgehog. The upper molars of the shrews lack the fifth 

 cusp found in the first two of these teeth in the hedgehogs. 



The shrews are not only more numerous in genera and species than any 

 other family of the order to which they belong, but have likewise a much 

 wider geographical distribution, being found over the greater part of Europe. 



