Morton's theories were very popular in his day, and he was a highly respected physician and scientist.
Morton claimed in his Crania Americana that the Caucasians had the biggest brains, averaging 87 cubic inches (1,426 cc), Indians were in the middle with an average of 82 cubic inches (1,344 cc) and Negroes had the smallest brains with an average of 78 cubic inches (1,278 cc) [REF].