51 



and opposable to the others. Dental series interrupted by diastemas, 

 especially in the upper jaw between canines and incisors. Hair dense. 

 (Simice.) 



A. A bony external auditory meatus well developed, at the bottom of 

 which is the membrana tympani. Pre-molars 2 ,x2. (Teeth M § PM | 

 C j I §X2.) Nose with the median septum thin and narrow (exception- 

 ally, broad), and the nostrils correspondingly approximated. (Simice 

 catarrhinos.") 



1. Spinal column with a slight sigmoid curve ; lumbar as well as dorsal 

 neural spines directed more or less backwards. Sacrum large and 

 solid, composed of four vertebra? tapering gradually backwards. 

 Sternum broad and short, with three or four bones between the manu- 

 brium and xiphoid cartilage. Anterior limbs much longer than 

 posterior. 



SIMIIDAE. (II.) 



2. Spinal column with a simple curve ; neural spines of lumbar and 

 last dorsal vertebra? inclined forwards. Sacrum moderate, composed 

 generally of three vertebra? not tapering gradually. Sternum elongated 

 and narrow. Anterior limbs shorter than posterior ; rarely elongated. 



CYNOPITHECIDAE. (III.) 



B. Bony external auditory meatus null, and the tympanic membrane 

 attached to a ring close to the surface. Pre-molars |x2. Nose with 

 the septum broad and flattened (exceptionally, narrow), and the nostrils 

 proportionally distant. (Simice platyrkince.) 



1. Teeth (M l-PMf CJI|x2=) 33. Manus with inner digit (when 

 developed) more or less slightly opposable to the rest. 



CEBIDAE. (IV.) 



2. Teeth (M | PM f C ] I |X2=) 32. Manus with inner digit not 

 opposable, but on same plane as rest; all armed with elongated com- 

 pressed claws. 



MIDIDAE. (V.) 



I. HOMINIDAE. 



Single genus. 



Homo. 



II. SIMIIDAE. 



SUB-FAMILIES. 



I. Form robust. Ilia broad, alate. Cerebrum projecting backwards over 

 the cerebellum. Buttocks without callosities. 



SIMI1NAE. (A.) 



II. Form slender. Ilia narrow, not alate. Cerebrum scarcely or not pro- 

 jecting backwards over the cerebellum. Buttocks with callosities. 



HYLOBATINAE. (B.) 



