This conclusion is based on the relative achievements of the race; it must be tested by the more precise methods of the anthropological laboratory. Satisfactory studies of the Negro should be much more numerous, but there are a few informative ones. Physical characters are first to be considered.
As a result of the careful measurement of many skulls, Karl Pearson[134] has come to the following conclusions:
"There is for the best ascertainable characters a continuous relationship from the European skull, through prehistoric European, prehistoric Egyptian, Congo-Gaboon Negroes to Zulus and Kafirs.
"The indication is that of a long differentiated evolution, in which the Negro lies nearer to the common stem than the European; he is nearer to the childhood of man."
This does not prove any mental inferiority: there is little or no relation between conformation of skull and mental qualities, and it is a great mistake to make hasty inferences from physical to mental traits. Bean and Mall have made studies directly on the brain, but it is not possible to draw any sure conclusions from their work. A. Hrdlička found physical differences between the two races, but did not study traits of any particular eugenic significance.
On the whole, the studies of physical anthropologists offer little of interest for the present purpose. Studies of mental traits are more to the point, but are unfortunately vitiated in many cases by the fact that no distinction was made between full-blood Negroes and mulattoes, although the presence of white blood must necessarily have a marked influence on the traits under consideration. If the investigations are discounted when necessary for this reason, it appears that in the more elementary mental processes the two races are approximately equal. White and "colored" children in the Washington, D. C., schools ranked equally well in memory; the colored children were found to be somewhat the more sensitive to heat.[135] Summing up the available evidence, G. O. Ferguson concludes that "in the so-called lower traits there is no great difference between the Negro and the white. In motor capacity there is probably no appreciable racial difference. In sense capacity, in perceptive and discriminative ability, there is likewise a practical equality."
This is what one would, a priori, probably expect. But it is on the "higher" mental functions that race progress largely depends, and the Negro must be judged eugenically mainly by his showing in these higher functions. One of the first studies in this line is that of M. J. Mayo,[136] who summarizes it as follows:
"The median age of white pupils at the time of entering high school in the city of New York is 14 years 6 months: of colored pupils 15 years 1 month—a difference of 7 months. The average deviation for whites is 9 months; for colored 15 months. Twenty-seven per cent of the whites are as old as the median age of the colored or older.
"Colored pupils remain in school a greater length of time than do the whites. For the case studied [150 white and 150 colored], the average time spent in high school for white pupils was 3.8 terms; for colored 4.5 terms. About 28% of the whites attain the average time of attendance for colored.
"Considering the entire scholastic record, the median mark of the 150 white pupils is 66; of the 150 colored pupils 62; a difference of 4%. The average deviation of white pupils is 7; of colored 6.5. Twenty-nine per cent. of the colored pupils reach or surpass the median mark of the whites.