measurements varied from each other but slightly. In confirmation of this result it is worthy of notice that the mean vertical diameter of the twenty-one mound and stone grave crania from Tennessee varied from that of the Mexican crania by only one one-hundredth of an inch (5.56). When Dr. Morton began his investigations, he was disposed to recognize the existence of distinct races, represented by the dolichocephalic and brachycephalic crania of Peru.[248] But in later years, and at a period subsequent to the issue of his justly celebrated work, he concluded that the Peruvian elongated head was the product of artificial compression and not the distinguishing mark of an ancient race which long antedated the Incas.[249] Prof. Wilson has thoroughly discussed this subject, and from a series of investigations, conducted on a much more extensive scale than those of Dr. Morton, he has shown conclusively that the distinguished craniologist was quite mistaken as to the facts upon which he based his later views.[250] Much valuable information was afforded Prof. Wilson by the researches and collections of John H. Blake, Esq., made during that gentleman’s residence in Peru, as well as the extensive collection of Dr. J. C. Warren of Boston. Prof. Wilson points out the essential difference between the compressed and the naturally dolichocephalic cranium in these words: “Few who have had extensive opportunities of minutely examining and comparing normal and artificially formed crania, will, I think, be prepared to dispute the fact that the latter are rarely, if ever, symmetrical. The application of pressure on the head of the living child can easily be made to change its natural contour, but it cannot give to its artificial proportions that harmonious repetition of corresponding developments on opposite sides which may be assumed as the normal condition of the unmodified cranium. But in so extreme a case as the conversion of a brachycephalic head averaging about 6.3 inches longitudinal diameter by 5.3 inches parietal diameter into a dolichocephalic head of 7.3 by 4.9 inches diameter, the retention of anything like the normal symmetrical proportions is impossible. Yet the dolichocephalic Peruvian crania present no such abnormal irregularities as could give plausibility to the theory of their form being an artificial one, while peculiarities in the facial proportions confirm the idea that it is of ethnic origin and not the product of deformation.” Besides these differences there are peculiarities of a structural nature sufficient in themselves to distinguish the Peruvian long from the short crania. The former is small, narrow and decidedly long; the forehead is low and retreating, and two-thirds of the brain-cavity lies behind the occipital foramen. The superior maxillary is protruding and holds the incisor teeth obliquely. The weight of the bony structure also exceeds that in the brachycephalic.