200 



LEMURS. 



thumb and great toe ; but, curiously enough, in some of them the index finger of 

 the hand is rudimentary. They may or may not have tails, but these are never 

 prehensile, although, as in some of the marmosets, they may be marked by alternate 

 dark and light rings. 



A point of resemblance to the monkeys and apes is shown by the number of 

 incisor, or front teeth, being very frequently two on each side of both jaws, in 

 place of the three which are so commonly present in other Mammals. In the 

 apes and monkeys, however, the central pair of incisors in the upper jaw are in 



SKELETON OF SQUIRREL-MONKEY (1), OF MONGOOSE LEMUR (2), AND OF SLENDER LORIS (3). 



contact with one another, while in the lemurs they are almost invariably separated 

 by a gap in the middle line. This affords a ready means of distinguishing the skull 

 of a lemur at a single glance from the skulls of almost all other Mammals except 

 bats and some of the Insectivores. The lower front, or incisor, teeth of the 

 lemurs shelve forwards, after the manner we have already mentioned as character- 

 istic of one group of the American monkeys (p. 173). 



Many lemurs are purely nocturnal animals, and it was probably from this cir- 

 cumstance, coupled with their silent habits and stealthy movements, that Linnaeus 

 was induced to give them the najne by which they are now universally known. 

 It is, perhaps, almost superfluous to mention that the name lemur is taken from 

 the Latin term lemures, which, together with that of larvce, was applied by the 



