Prof. J. D. Dana on the Classification of Mammals. 207 



XXIII. — On the higher Subdivisions in the Classification of 

 Mammals. By James D. Dana*. 



The precise position of Man in the system of Mammals has 

 long been, and still remains, a subject of discussion. There are 

 those who regard him as too remote from all other species of the 

 class to be subject to ordinary principles of classification. But 

 zoologists generally place him either in an independent order (or 

 subclass, if the highest divisions be subclasses) or else at the head 

 of the order containing the Quadrumana. Science, in searching 

 out the system in nature, leaves psychical or intellectual quali- 

 ties out of view ; and this is right. It is also safe ; for these 

 immaterial characteristics have, in all cases, a material or struc- 

 tural expression; and when this expression is apprehended, and 

 its true importance fully admitted, classification will not fail of 

 its duty in recognizing the distinctions they indicate. 



Cuvier, in distinguishing Man as of the order Bimana, and the 

 Monkeys of the order Quadrumana, did not bring out to view 

 any profound difference between the groups. The relations of 

 the two are so close that Man, on this ground alone, would be 

 far from certain of his separate place. No reason can be derived 

 from the study of other departments of the Mammals, or of the 

 animal kingdom, for considering the having of two hands a 

 mark of superior rank "to the having of four. 



Prof. Owen, in his recent classification of Mammals f, makes 

 the characteristics of the brain the basis of the several grand 

 divisions. But, as he admits, the distinctions fail in many cases 

 of corresponding to the groups laid down; and although the 

 brain of Man (his group Archencephala) differs in some striking 

 points from that of the Quadrumana, yet no study of the brain 

 alone would suggest the real distinction between the groups, or 

 prove that Man was not coordinal with the Monkeys. In fact, 

 the nervous system is a very unsafe basis of classification below 

 the highest grade of subdivisions — that into subkingdoms. The 

 same subkingdom may contain species with, and without, a di- 

 stinct nervous system, and a class or order may present very 

 wide diversities as to its form and development, for the reason 

 that the system or plan of structure in species is far more 

 authoritative in classification than the condition of the nervous 

 system. 



The fitness of the parts of the body of Man for intellectual 

 uses, and his erect position, have been considered zoological 



* From the American Journal of Science and Arts, vol.xxxv. Jan. 1863. 

 Communicated by the Author. 



f Journal of the Proceedings of the Linnean Society of London, for 

 Feb. 17 and April 21, 1857. 



