506 QUADRUMANA. 



Rejecting, however, these trivial characters, and influenced in 

 his views by the part which the long tail of the species in question, 

 exercises as a balancer in their arboreal movements, a talented naturalist* 

 separates them from the Macaci with short or tuberculous tails, and 

 places them in the genus Cercopithecus, while, sinking entirely the term 

 Macacus, he substitutes a genus, termed Papio,-}- for the reception of the 

 remaining species. The principle by which this naturalist is here 

 guided, is briefly this : that no characters can, with propriety, be received 

 as generic, except such physical modifications as are palpably subservient 

 to some design, and, therefore, are attended by a corresponding modifica- 

 tion of habits and manners, a proposition which would have irresistible 

 weight, could the real value of structural modifications be always 

 determined; and did not anatomical minutiae necessarily guide the 

 naturalist, even where the express results of these minutiae cannot be 

 demonstrated. Hence it is that genera are founded upon the presence or 

 absence of lachrymal sinuses, or inguinal pores, though their use and 

 influence in the animal economy are not understood ; and hence it is that, 

 upon the number of toes, genera are established, though no results from 

 a variation in this particular are to be perceived. Moreover, it would 

 appear that characters, trifling in themselves, gain, from their universality 

 and permanence, a value which they might not otherwise possess, and 

 thus, notwithstanding the presence of the fifth tubercle in the lower 

 jaw of the Collared and Sooty Monkeys (which may justly be placed 

 under a sub-generic head), the genus Macacus, confined to India, with 

 the exception alluded to, but containing certain sub-genera, may be 

 received as based on sufficient warranty. The long-tailed Macaci, con- 

 stituting a sub-genus, may be, indeed, regarded as the representatives of 

 the African Cercopitheci ; and the short- tailed species, of the Cynocephali ; 

 while, among these latter, the Magot, a native of the North of Africa and 

 its districts, most adjacent to Asia, may form the type of a sub-generic 

 section. 



GENUS. CERCOPITHECUS. 



Cercopilhecus ERXLEBEN, in part Syst. Regni Anim. 1777. 



GENERIC CHARACTERS. MUZZLE moderately prominent; the FACIAL 

 ANGLE 45 50 ; HEAD round ; SUPERCILIARY RIDGE moderate ; MOLARS 

 crowned with acute tubercles ; LAST MOLAR of the lower jaw with only 

 four tubercles; CHEEK -POUCHES usually ample; LARYNGAL SAC 



* See Menageries in Library of Entertaining Knowledge, vol. xlii. part ii. 



t This term, as a generic title, has been previously applied by Geoffrey, to the Cynocephali, in Ann. 

 du Mus. vol. xix. ; and also by Kuhl and Erxleben. 



