182 PHYSICAL INVESTIGATION. [PART I. 



deavoured to establish the one, that the crossing of different types 

 invariably induces a physical and moral degeneration, and im- 

 plants the germ of certain decay, whilst Serres considers cross- 

 ing as an essential means of improving the race, and rendering it 

 vigorous by the infusion of fresh blood from a different stock : 

 he is even inclined to believe that in a perfect intermixture of the 

 chief types is a solution of the problem of the development of 

 humanity. Nott, who thinks to have demonstrated the exist- 

 ence of various human species, endeavours also to prove that 

 mongrels possess little viability, and only a limited prolificacy, 

 and are incapable by themselves of founding a new type, since 

 they have no permanent vitality without re-crossing with 

 one of the parent stocks. It will presently be shown that 

 this theory is as little consonant with the facts as the pre- 

 ceding. 



Whatever view we may adopt with regard to the unity of the 

 human species, it would be idle to expect that the mongrels of 

 the various types should be equally viable and vigorous, since 

 there are peoples apparently unmixed who are more or less 

 strong or weak, according to their constitution, mode of life, 

 and climate. Corresponding differences are found in mongrel 

 races. In some cases the mongrels of different stocks are more 

 prolific and vigorous than the stock from which they issued. 

 The Kuruglis (mongrels of Turks and Moors) excel their 

 Turkish fathers in strength and beauty of form. 1 Arabs and 

 Ethiopians (Abyssinians and their allied tribes) produce a fine 

 race, viable in all warm climates. 2 From the intermixture of 

 Europeans with the natives of the Philippines there frequently 

 issue finer children than those produced by the marriages of 

 Europeans between themselves. 3 D'Orbigny is of opinion, 

 that, by the intermixture of various Indian tribes of South 

 America, healthier and more gifted individuals are produced ; 

 but he does not think that such is the case when Europeans 

 ally themselves with the natives of those regions. The mixed 

 populations of Paraguay, existing in a similar healthy con- 



1 M. Wagner, " E. in Algier," iii, p. 293, 1841. 



2 Pruner, p. 71. 



3 Mallat, ii, p. 40. 



