THE VARIETIES OF THE HUMAN SPECIES. 



PRINCIPLES AND METHOD OF 

 CLASSIFICATION. 



By Giuseppe Sergi. 



PART FIRST. — Basis of Human Classification, 



I. 



In man, as in other animals, we find physical characteristics of 

 two kinds, external and internal. The first are principally those 

 pertaining to the cutis and certain cutaneous appendages, and 

 include the coloring of the skin and hair, the structure and form 

 of the hair, and also the coloring of the eyes. The chief internal 

 characteristics are the bones from which the form and figure of all 

 the members are taken, as well as those of the separate parts of the 

 body clothed with soft tissues, such as muscles and fat. The 

 cranium is the most important and most characteristic part of the 

 entire human skeleton. 



The cranium is a bony case which encloses a viscus of the first 

 order, the brain, which in man is, in relation to the animal series, 

 better developed, both in its forms and functions. It is known 

 that the brain and cranium, from the embryological to the adult 

 state, are in a parallel manner and gradually connected in evolu- 

 tion, and the external form of the one corresponds to that of 

 the other. Most certainly it is not the cranium which gives form 

 to the brain of man; it is more probable that it is the brain 

 which moulds its organ of protection. Given hereditary condi- 

 tions, we may affirm that the form of the cranium is correlative to 

 that of the brain. If we could discover why the brain takes or 

 has taken different forms we would possibly understand better its 

 corespondence with the exterior structure of the cranium by which 

 it is surrounded, though absolutely ignorant now. We might be 



