578 LAND MAMMALS IN THE WESTERN HEMISPHERE 



Suborder LEMUROIDEA. Lemurs 



I. fNoTHARCTID.E. 



'\ Pelycodus, low. and mid. Eoc. \ Notharctus, Eoc. 

 11. IAnaptomorphid.e. 



^Anaptomorphiis, low. and mid. Eoc. \Omomys, mid. Eoc. 

 \ Hemiacodon, do. 



Suborder ANTHROPOIDEA. Monkeys, Apes, Man 



Section Platyrrhina 



III. Hapalid^. Marmosets. 



Hapale. Pleist. and Rec. Midas, Rec. 



IV. Cebid^. South American Monkeys. 



Cebus, Pleist. and Rec. Alouatta, Howling Monkeys, Pleist. and 

 Rec. Ateles, Spider Monkeys. Pithecia, Sakis. Cacajao, 

 Uakaris. Nydipithecus, Donroncoulis. t-E"*'* odes, Pleist. f-^^- 

 munculus, Santa Cruz. \Pithecidus, do. 



The existing Primates are divided into two suborders, 

 Lemuroidea and Anthropoidea, which are quite clearly distin- 

 guished from each other, but the fossil forms largely efface the 

 distinction. 



Suborder Lemuroidea. Lemurs 



The name Lemur, which Linnaeus gave to a genus of this 

 suborder, signifies in Latin a spectre or ghost and was prob- 

 ably suggested by the very strange appearance and nocturnal 

 habits of these curious creatures. The term has been adopted 

 as the English name for the group, as there was no vernacular 

 word for it. The lemurs are very obviously the more primitive 

 division of the Primates. Omitting for the present the extinct 

 forms, the dental formula is usually : i |, c\, p f , r?i f , X 2 =36 ; 

 the upper canine is a long, sharp, dagger-like tooth, but the lower 

 one, in nearly all of the genera, is like an incisor and its place is 

 taken by the anterior premolar ; the premolars are simple, 

 compressed and trenchant and the upper molars tritubercular. 

 The skull usually has a long and tapering facial portion, so 

 that the living head has some resemblance to that of a raccoon. 

 The orbits almost always have a more or less lateral presenta- 



