THE MINGLING OF RACES 557 



they do not lay it on readily, or are easily disturbed in 

 their alimentary functions by overfeeding, and return 

 readily to their normal weight after the super-feeding, 

 which they generally find distasteful, has ceased. On the 

 other hand, persons derived from a union of two famihes 

 in which fleshiness is common often find (i) that they have 

 fairly large appetites and (2) that they tend to lay on flesh, 

 even with moderate feeding, (3) that they are tolerant of 

 large amounts of food and, (4) that dieting and exercise are 

 able to reduce their build only slowly and with great difficulty. 

 Nevertheless, the fact that variations in food ingestion 

 play some part in body build comphcates the study of 

 inheritance of this trait. 



Not only physical traits, hke eye color, skin color, body 

 build and such characters as stature, color and form of the 

 hair, proportions of facial features and many others are 

 inherited in race-crosses but also mental traits. This is a 

 matter which is often denied, but the apphcation of methods 

 of mental measuring seem to have produced indubitable 

 proof that the general intelHgence and specific mental 

 capacities have a basis and vary in the different races of 

 mankind. Thus it has been shown, by standard mental tests, 

 that the negro adolescent gained lower scores than white 

 adolescents and this when the test is made quite independent 

 of special training or language differences and also when 

 the children tested have a similar amount of schooling. 

 Not only the psychological examination in the army but 

 also the special studies made by Mayo and others, working 

 in the Department of Psychology at Columbia, and many 

 other investigations are agreed in this result. On the other 

 hand, it seems probable that, in the matter of sense percep- 

 tion and discrimination, the negro race is, in general, 

 superior to the whites. Tests made on whites and negroes in 

 Jamaica indicate that the negroes are superior in their 

 ability to discriminate slight differences in musical pitch, 

 intensity and time. There is no doubt, in view of the studies 

 of Dr. Hazel M. Stanton, that differences in capacity for 

 such discriminations are inherited and we can, therefore, 

 understand the more readily how they may become racial 

 traits. 





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