614 



THE PRIMATES 



xxiii. 5- 



primates, but may be close to both. *Plesiadapis is the only primate 

 genus except Homo that occurs in both Old and New Worlds. 



The Adapidae were also Palaeocene and Eocene animals, like lemurs 

 in many ways but without procumbent incisors. The Old World 

 members of the family (* Adapts) could have given rise to both the 



lemurs and lorises. The adapids 

 were large creatures with heads 

 a foot or more long. The brain 

 case was small (*Notharctus, 

 Fig. 387) but carried temporal 

 crests. There was a very full 



dentition ( *'' ). The incisors 

 2.1.4.3 



were not procumbent but the 

 canines were incisiform. The 

 tympanic ring was included in 

 the bulla. These animals there- 

 fore showed many features 

 common to other early mam- 

 mals but with distinctly lemur- 

 oid tendencies. 



6. Tarsiers 



The third group of the 

 Prosimii, the Tarsiiformes, in- 

 cludes one living form, Tarsius, 

 and a number of early Tertiary 

 fossils, placed in a separate 

 family *Anaptomorphidae. 

 The whole group could be described by saying that its members 

 show many characteristics similar to those of Insectivora and lemurs, 

 but also others suggestive of the anthropoid primates. Yet there are 

 present specializations that rule out the possibility that these animals 

 are in the direct line of descent of the higher forms, and we must 

 therefore regard them as an early offshoot, showing us something of 

 the characteristics that were possessed by the anthropoid stock in 

 Palaeocene or early Eocene times. 



Tarsius itself (Fig. 393) is an arboreal, nocturnal, insectivorous 

 creature, the size of a small rat, living in the East Indian islands. The 



2.1 ."2. T 



dental formula is — '^-^ ; the molars retain a very simple tritubercular 

 i-T-3-3 



Fig. 393. Spectral tarsier, Tarsius. 

 (From life.) 



