228 APES, MONKEYS, AND LEMURS 



THE SLOW LEMURS, OR LORIS 

 Genera Nycticebus and Loris 



With the slow lemurs of the warmer parts of Asia we come to the last group 

 of the lemur family ; this group likewise including the pottos of Africa, to be 

 described next. The members of this group may be recognized either by the total 

 absence of the tail, or by its length not exceeding one- third that of the head and 

 body. The only lemur with which these animals could possibly be confounded 

 would, therefore, be the indri of Madagascar ; but, irrespective of its larger size, 

 that animal is at once distinguished by the web uniting the bases of the toes, and 

 the full development of the index finger of the hand. Moreover, the slow lemurs 

 and the pottos may be further distinguished, not only from the indri, but likewise 

 from all other lemurs, by the index finger of the hand being invariably very small, 

 and even rudimentary and without any trace of a nail. Then, again, all these 

 lemurs are peculiar in having the thumb of the hand and the great toe of the foot 

 very widely separated from the other digits ; this divergence being carried to such 

 an extent in the case of the great toe, which is actually directed backward instead 

 of forward. 



Apart, therefore, from their distribution, there is no difficulty in distinguishing 

 a slow lemur or a potto from all other lemurs. All the members of the present group 

 have, however, the same number of teeth as the true lemurs, but they differ from 

 the galagos and mouse-lemurs in that the bones of the upper part of the ankle are 

 of ordinary proportions, so that the foot is not abnormally lengthened. 



The slow lemurs are purely nocturnal, and are well known for the extreme 

 slowness and deliberation of their movements ; the latter characteristic having given 

 their distinctive name to the Asiatic representatives of the group. It was probably 

 their deliberate motions, nocturnal habits, and large glaring eyes, that suggested to 

 the Swedish naturalist Linnaeus the name of lemur for the group generally. 



The slow lemurs are distinguished from the pottos by having a well-developed 

 but small index finger on the hand, which has the usual three joints, and is provided 

 with a distinct nail. They have no external tail, and are, as we have already men- 

 tioned, strictly confined to the tropical and subtropical regions of Asia. There are 

 three species, all of which are very closely allied, although the majority of natural- 

 ists have considered it advisable to divide them into two genera, one of which con- 

 tains two, and the other one species. 



THE COMMON LORIS {Nycticebus tardigradus) 



The common loris, or slow lemur, may be taken as the typical representative of 

 the genus Nycticebus. The distinctive features of this animal, as the representative 

 of a genus, are that the eyes are not of very enormous size, and are separated from 

 one another by a considerable space ; while the general build of the animal more 

 especially as regards its limbs is comparatively stout. 



