THE DESCENT OF THE PEIMATES 11 



flat nails to the fingers. These are however 

 replaced on two fingers of the hindfoot by hooked 

 claws, the Lemurs having only one finger thus 

 exceptionally provided. 



On the contrary, a whole family (Arctopitheci) 

 of monkeys have a more considerable number of 

 claws instead of nails, and an opposable thumb 

 to only the hinder of the four extremities, so 

 that we see that even this most prominent point 

 of resemblance can claim only a restricted taxo- 

 nomical value. Systematists have undoubtedly 

 been led by the peculiar external aspect, perhaps 

 even by the nocturnal habits, to approach Tar- 

 sius so closely to the Lemuroids. At the same 

 time they have never failed to recognize it either 

 as " une espfece anormale " ^ or as " a very aber- 

 rant form." 2 



Indeed, in very many respects Tarsius does 

 not fit in with the Lemurs at all. Its dentition 

 is much more archaic. Its upper and lower 

 incisors, especially the latter, as well as its 

 canine teeth, resemble more closely those of the 

 Insectivora than they do the modified and spe- 

 cialized incisors of the Lemurs. And its molar 



1 H. Schlegel, Museum d'Histoire naturelle des Pays-Bas, 

 Tome VIL, Leyde, 1876, p. 331. 



2 Flower and Lydekker, Mammalia, Liviug and Extinct, 

 London, 1891, p. 683. 



