white pupils. He concludes: "In general the marks indicating mental ability of the Negro are about two-thirds those of the whites.... In the substitution, controlled association, and Ebbinghaus tests, the Negroes are less than half as good as the whites. In free association and the ink-blot tests they are nearly as good. In quickness of perception and discrimination and in reaction, the Negroes equal or excel the whites."
"Perhaps the most important question that arises in connection with the results of these mental tests is: How far is ability to pass them dependent on environmental conditions? Our tests show certain specific differences between Negroes and whites. What these differences would have been had the Negroes been subject to the same environmental influences as the whites, it is difficult to say. The results obtained by separating the Negroes into two social groups would lead one to think that the conditions of life under which the negroes live might account for the lower mentality of the Negroes. On the other hand, it may be that the Negroes living under better social conditions are of better stock. They may have more white blood in them."
The most careful study yet made of the relative intelligence of Negroes and whites is that of G. O. Ferguson, Jr.,23 on 486 white and 421 colored pupils in the schools of Richmond, Fredericksburg, and Newport News, Va. Tests were employed which required the use of the "higher" functions, and as far as possible (mainly on the basis of skin-color) the amount of white blood in the colored pupils was determined. Four classes were made: full-blood Negro, ¾ Negro, ½ Negro (mulatto) and ¼ Negro (quadroon). It was found that "the pure Negroes scored 69.2% as high as the whites; that the ¾ pure Negroes scored 73.2% as high as the