MAMMALIA. 339 



9th Order. QUADRUMANA. The existence of this order 

 in a fossil state is a recent discovery, and it is remarkable, 

 that about the same time the remains of monkeys were found 

 in the tertiary strata of Europe, Asia, and America. The 

 quadrumana are characterised by the four hands which 

 terminate their extremities, in each of which the thumb is 

 opposable to the fingers. They have incisor, canine, and 

 molar teeth. In the general structure of their skeleton in 

 the development of their brain, nervous system, and the organs 

 of the senses, as well as in their digestive organs they ap- 

 proach near to man. We divide the order into two tribes : 



1st Tribe. The monkeys of the Old World, which have 

 twenty molars. 



2nd Tribe. The monkeys of the New World, which have 

 twenty-four molars. 



The Monkeys of the Old World have, like man, four vertical 

 incisors. Two canine, and ten molars in each jaw. To 

 this tribe belongs the jaw of the 3acacus, 

 obtained from the eocene sand of Kyson, in 

 Suffolk, of which we subjoin the figures 250 

 and 251, and description, given by Professor 

 Owen, in whose hands the specimen was 

 placed for identification : * 



" The fossil exhibits the following differ- 

 ences from the recent Macaci : The whole FIG. 250. jaw and 

 tooth is rather narrower in proportion to its SSurai s'Sef" 5 " 8 ' 

 length ; the transverse ridge at the anterior 

 part of the tooth, crossing the base of the two anterior tuber- 

 cles, is a little more prominent, and passes more obliquely 

 from the outer to .the inner side ; the second transverse ridge, 

 uniting the first pair of tubercles, rises nearer to their 

 summits. The portion of jaw is more compressed than the 

 corresponding part of the jaw in the recent Macaci (compare 

 fig. 251, J9.) ; the internal wall of the socket of the tooth is 

 flatter and much thinner ; (this character of the fossil is 

 well shown in fig. 251, C,) ; the ridge on the outer side of the 

 alveolus, which forms the commencement of the anterior 

 margin of the coronoid process, begins closer to the tooth (as 

 is shown in figs. 250 and 251, A). 



* Mag. of Nat. History, vol. iii., New Series, page 446. 



z2 



