MANUAL OF NATUEAL HISTORY. 13 



I._CLASS MAMMALS (Mammalia}. 



Faculties in most advanced state of perfection; 

 powers of motion varied ; sensations delicate ; intel- 

 ligence superiorly developed ; young suckled; mostly 

 fitted for walking; a few are enabled to fly, and 

 some are destined to live in the water. 



1. SUB-CLASS. PL ACENTAL MAMMALS 

 (Placentaiia). 



I. ORDER. MAN (Primates). 

 Position of body vertical ; senses delicate, and 

 nicely balanced ; organs of voice pre-eminent; intel- 

 ligence in a high degree ; capable of progressive de- 

 velopment. 



1. FAMILY. Men (Hominidse). Characters as in 

 Order. 



II. ORDER. FOUR-HANDED MAMMALS (Quadrumana). 



Limbs more or less lengthened ; possess four or- 

 gans of prehension similar to hands, generally with 

 an opposable thumb on each. 



1. FAMILY. Apes (Simiidse). Nostrils divided by a 



narrow septum ; opposable thumbs on fore 

 and hind feet ; generally naked callosities on 

 rump ; sometimes cheek pouches ; usually 

 furnished with a tail. Dentition incis : J 

 can. i = J pre mol: mol: tJ=32. 



2. FAMILY. American Monkeys (Cebidse). Nos- 



trils separated by a broad septum; thumbs 

 sometimes absent on fore feet ; no callosities 



