QUADRUPEDS. 173 



Grinders twenty in number. 



A. Nails of the fingers and toes, flat and rounded. 



(a.) Destitute of a tail. 



a. No cheek pouches. The liver, caecum and os hyoides, 

 resemble those in Man. 



2. MiMETES (of Dr Leach,) Chhnpanse. There is no in- 

 termaxillary bone ; the last joint of the great toe is perfect, 

 and the thigh-bone has the ligamentum suspensorium. The 

 Simia troglodytes of authors, is the type of the genus. 



3. Simia. Orang-Outang. There is here an intermaxil- 

 lary bone ; but the last joint of the great toe, and the sus- 

 pensatory ligament of the thigh-bone are wanting. The 

 Simia Satyrus is the type *. 



h. With cheek-pouches. 

 4. PoNGOs. This genus contains only one species, from 

 the Island of Borneo. 



(b.) Furnished with a tail. With cheek-pouches, and cal- 

 lous buttocks. 



a. The last grinders in the lower jaw, -with four tubercles. 

 5. Cercopithecus. This genus, which contains many 



species, will probably require to be subdivided. The 

 Kahau of Bornea, C. nasicus, appears to constitute a genus 

 apart. 



b. The tubercles in the last grinders of the lower jaw un- 

 equal. 



6*. Pithecus. This includes the Magot and Macaques 

 of CuviER, and is distinguished from the following genus, 

 by the oblique position and dorsal aspect of the nostrils. 



Ais foramen prevents the inconvenience of too intense a light, if it is proba- 

 ble that it expands and dilates a little, and thus removes the principal focXis 

 from the very sensible centre of the retina."— Institutes of Phys,, Note, 

 p. US. 



* Annals of Phil. xvi. p. lO'l. 



