Mat 28, 1909] 



SCIENCE 



845 



Asia Minor, who are the descendants of 

 intermarriages between a short-headed 

 type of the central parts of Asia Minor 

 and of the long-headed south coast type — 

 a miKture which has contiriued for thou- 

 sands of years — show clear evidence of 

 alternatiag inheritance. In 1895 I was 

 able to show (utilizing fairly extended ob- 

 servations) that the mixed blood resulting 

 from unions of American Indians and 

 whites shows, in regard to certain traits, 

 a clear tendency to reversion to either 

 parental type; while in other respects (for 

 instance, in stature) new characteristics 

 seem to develop. A recent inquiry into 

 heredity among east European Jews shows 

 that here also the children show a tendency 

 to revert either to the father's or to the 

 mother 's type. This result is interesting, be- 

 cause it bears upon unions inside of a fairly 

 uniform type of man. Other observations 

 relate to the inheritance of abnormal traits, 

 all of which seem to suggest, if not true 

 Mendelism, at least the occurrence of alter- 

 nating inheritance. However, the obser- 

 vations on mixtures of Indian and white 

 have shown that while alternating in- 

 heritance may be found ia regard to such 

 traits as the form of the head and face, 

 the development of the bulk of the body 

 follows different laws. Notwithstanding 

 these observations, the whole problem of 

 the effects of race intermixture upon the 

 various characteristic traits of human 

 types is entirely unsolved. 



It is not too much to say that the whole 

 Vork in this field remains to be done. "We 

 do not know what weight to give to the 

 small differences of types such as are 

 found in Europe, and whether these differ- 

 ences are sufiSciently great to be considered 

 important as compared with the differences 

 between individuals of the same geograph- 

 ical type but belonging to opposite ends of 

 the local series. We must not forget that 

 the people of Europe ia each locality are 



very variable, and that we may find (for 

 instance, in Scotland) considerable num- 

 bers of individuals who will differ from one 

 another more than do the average individ- 

 uals of, let me say, Scotland and southern 

 Italy. The question of the effects of 

 intermixture of types can, therefore, 

 not be treated entirely separately from 

 the question of intermarriages among 

 people belonging to the same locality. 

 And it is worth considering whether 

 the remoteness of blood relationship in 

 different parts of Europe, as compared 

 to the closer blood relationship inside 

 of a narrow territory, may not outweigh 

 all the influences of the differences of 

 geographical types. The whole question 

 seems to be most complex, and worthy 

 of the most detailed and thorough study; 

 but I do not venture to predict the ana- 

 tomical and physiological effects of inter- 

 mixture without a most painstaking iu- 

 vestigation, which has not been made up 

 to this time. 



Considering our lack of knowledge of 

 the most elementary facts that determine 

 the outcome of these processes, I feel that 

 it behooves us to be most cautious in our 

 reasoning, and particularly to refrain from 

 all sensational formulations of the prob- 

 lem, that are liable to add to the prevalent 

 lack of calmness in its consideration; the 

 more so since the answer to these questions 

 concerns the welfare of millions of people. 



The problem is one in regard to which 

 speculation is as easy as accurate studies 

 are difficult. Basing our arguments on 

 ill-fitting analogies with the animal and 

 plant world, we may speculate on the 

 effects of intermixture upon the develop- 

 ment of new types — as though the mixture 

 that is taking place in America were in 

 any sense, except a sociological one, differ- 

 ent from the mixtures that have taken 

 place in Europe for thousands of years; 

 looking for a general degradation, for re- 



