IN THE HUMAN SPEC IKS. 261 



mon race, the offspring generally is black. The same cir- 

 cumstance is seen in vegetables : the seeds of our fine cul- 

 tivated apples almost always produce tlie common crab ; 

 and the variegated holly can only be preserved as a variety 

 by grafting : when we attempt to propagate it by seed^ it 

 returns to the common green holly. In considering this as 

 an explanation of the mode in which varieties of colour may 

 have arisen in the human race, an objection will probably 

 occur, that we do not, in point of fact, see Negroes, Ame- 

 ricans, or Mongols, produced among the white races ; nor 

 Europeans among the former. The theory of unity of the 

 species would certainly be untenable, if it depended on 

 proving that such varieties occur. But the Negro and the 

 European are the two extremes of a very long gradation : 

 between them are almost innumerable intermediate stages, 

 which diiFer from each other no more than the individuals 

 occasionally produced in every race differ from the generality 

 of the race. 



That the common opinion, which refers the characteristic 

 differences of colour in the varieties of the human species 

 to climate, and particularly to the degree of solar heat, is 

 entirely unfounded, will, I trust, be fully proved hereafter. 

 Enough has now been said to shew that these differences 

 depend on the breed ; and that the hue of the offspring 

 follows that of the parents, excepting in the rare cases of 

 native or congenital variety. The latter examples prove that 

 colour is not an essential character of race ; that identity of 

 tint is not necessary to establish descent from a common 

 stock. These occurrences, together with the numerous ex- 

 amples of the widest deviation in colour in animals confess- 

 edly of the same species, fully authorize us to conclude, that, 

 however striking the contrast may be between the fair Eu- 

 ropean and the ebon African, and however unwilling the 

 Ibrmer may be to trace up his pedigree to the same Adam 

 with the latter, this superficial distinction is altogether in- 

 sufficient to establish diversity of species. 



Examples occur of individuals spotted with different 

 colours ; but they are by no means so common as those of 



