May 28, 1909] 



SCmNGU 



847 



is common— that this would result in a 

 rapid mixture of the descendants of various 

 nationalities. This inquiry, which it is 

 quite feasible to carry out in detail, seems 

 indispensable for a clear understanding 

 of the situation. 



It is somewhat difficult to realize how 

 rapidly intermixture of distinct types 

 takes place, if the choice of mates is left 

 entirely to accident. I have made this 

 calculation ; and I find that in a population 

 in which two types intermingle, and in 

 which both types occur with equal fre- 

 quency, there will be in the fourth genera- 

 tion less than one person in ten thousand 

 of pure descent. When the proportion of 

 the two original types is as nine to one, 

 there wiU be among the more numerous 

 part of the population only eighteen in 

 one thousand in the fourth generation that 

 will be of pure blood. Taking these data 

 as a basis, it is obvious that intermixture, as 

 soon as the social barriers have been re- 

 moved, must be exceedingly rapid; and I 

 think it safe to assume that one hundred 

 years from now, in the bulk of our popula- 

 tion, very few pure descendants of the 

 present immigrants will be found. 



Unfortunately, however, we do not know 

 the influence of racial cohesion. Obviously 

 this is one of the fundamental points that 

 ought to be known in order to gain a clear 

 insight into the effect of recent immigra- 

 tion. The data collected by our census 

 and by other agencies do not contain this 

 information, which is one of the most 

 urgent desiderata for an understanding of 

 the composition of the American popula- 

 tion. I may therefore express the hope 

 that this question may be included in the 

 census to be organized next year, or may be 

 otherwise provided for by an inquiry to be 

 undertaken under the auspices of the gov- 

 ernment. Without this information, the 

 whole discussion of the effect of intermix- 

 ture will remain speculative. 



No material whatever is available to 

 answer the question whether mixture of 

 types is favorable for the physical develop- 

 ment of the individual, or unfavorable. 

 Statistics collected in the Argentine Re- 

 public tend to show that with a mixture of 

 similar types, but from remote countries, 

 considerable changes in the proportions of 

 the sexes develop. Observations on half- 

 breed Indians show that a type taller than 

 either parental race develops in the mixed 

 blood ; that the fertility of the mixed blood 

 is increased ; and I can not find any evidence 

 that would corroborate the view, so often 

 expressed, that the hybrid of distinct types 

 tends to degenerate. 



I have refrained entirely from a discus- 

 sion of the social problem, which is no less 

 important than the one referring to the 

 physical types of the descendants of immi- 

 grants ; and I do not intend to include this 

 question in our consideration, which is de- 

 voted to the anthropological problem only. 



I have also devoted attention essentially 

 to the biological problems presented by the 

 immigration of European nations, but I 

 must not conclude my remarks without 

 referring at least to the serious problem 

 presented by the negro population of our 

 country. When compared with the contrast 

 between the negro and the white, the differ- 

 ences of the European types seem insignifi- 

 cant; and the unity of the European race, 

 as contrasted with the negro race, becomes 

 at once apparent. 



I do not intend to take up the whole ques- 

 tion of racial inferiority, which can not be 

 treated adequately in the brief time that I 

 can devote to this subject. I must confine 

 myself to a statement of my opinion, which 

 I have repeatedly tried to substantiate. I 

 do not believe that the negro is, in his 

 physical and mental make-up, the same as 

 the European. The anatomical differences 

 are so great that corresponding mental 

 differences are plausible. There may exist 



