3 1 2 IWSE CTIVORES. 



bats, which appear to be the ancestral groups of the order to which they belong, 

 having in all probability been directly derived from insect-eating Insectivores. 

 The cobego should, indeed, be regarded rather as the sole representative of a side 

 branch, which, while to some extent simulating the bats, never gave rise to any 

 descendants showing the special modifications for true flight. 



THE TREE-SHREWS, OR TUPAIAS. 

 Family TUPAIID^. 



With the tree-shrews, or tupaias, we come to the first family of the true 

 Insectivores, or those which are incapable of flight, and have their front or incisor 

 teeth of a normal form. 



The tree-shrews, which are entirely confined to the Oriental region, take their 

 name from their strictly arboreal habits; and are small, long-tailed animals, so 

 closely resembling the smaller squirrels in external appearance as to be frequently 

 mistaken for them. Indeed, it appears that the native term Tupai, from which 

 these animals derive their second title, is applied indifferently by the Malays both 

 to them and to squirrels ; the affix Tana serving to denote the members of the 

 present group. That they have really nothing to do with the squirrels is shown 

 by an examination of their teeth, when it will be found that, instead of the 

 single pair of chisel-like incisor teeth, they have two pairs of small incisors in 

 the upper jaw, and three pairs in the lower. 



The tree-shrews belong to a group of Insectivores characterised 

 Characteristics. ..:,,. , ' & , . fe , 



by their upper molar teeth, having broad crowns carrying a number 



of cusps, arranged in the form of the letter W. They are peculiar in that the 

 socket of the eye, or orbit, is surrounded by a bony ring, whereas in other members 

 of the order it is open behind. They are further distinguished from the other true 

 Insectivores not only by their completely arboreal, but likewise by their diurnal, 

 habits, as they feed entirely by day. They resemble squirrels in the general 

 form of the body and limbs, and in possessing a more or less bushy tail. 

 They have 38 teeth, of which are incisors, }- canines, and J cheek-teeth, on 

 either side of each jaw. Their feet, like those of squirrels, are naked beneath, 

 with moderately curved and sharp claws. The muzzle is sharply pointed, the ears 

 are small and rounded, and the long hair of the bushy tail is confined to its upper 

 surface and sides, the under-surface having much shorter hair. 



Altogether, there are about thirteen species of the genus 

 Tupaia, which have a wide distribution over the Oriental region. 

 They are found in India, Burma, the Malay Peninsula, the Nicobar Islands, 

 Sumatra, Java, Borneo, and the Philippines. They are very much alike in general 

 appearance, the species differing mainly in respect of size and colour, as well as 

 in the length of the fur. Many are restricted to particular islands ; the Bornean 

 tree-shrew, the Nicobar tree-shrew, and the recently discovered Philippine tree- 

 shrew, being unknown out of the islands from which they take their names. 

 Others, again, have even a still more restricted distribution ; two species having 

 hitherto been obtained only in the forests of Mount Dulit in North Borneo. 



