In accepting, however, the evidence for Tertiary man, we must accept with it conclusions which are much opposed to preconceived opinions. In the two best authenticated instances in which human skulls have been found in presumably Tertiary strata, those of Castelnedolo and Calaveras, it is distinctly stated that they present no unusual appearance, and do not go nearly as far in a brutal or pithecoid direction as the Quaternary skulls of Neanderthal and Spy, or as those of many existing savage races. The Nampa image also appears to show the existence of considerable artistic skill at a period which, if not Tertiary, must be of immense antiquity. How can this be reconciled with the theory of evolution and the descent of man from some animal ancestor common to him and the other quadrumana? Up to a certain point, viz. the earliest Quaternary period, the evidence of progression seems fairly satisfactory. If we take the general average of this class of skulls as compared with modern skulls, we find them of smaller brain-capacity, thicker and flatter, with prominent frontal sinuses, receding foreheads, projecting muzzles, and weaker chins. The brain is decidedly smaller, the average being 1150 cubic centimètres as compared with 1250 in Australians and Bushmen, and 1600 in well-developed Europeans; and of this smaller capacity a larger proportion is contained in the posterior part.[15] Other parts of the skeleton will tell the same story, and in many of the earliest and most extreme instances, as those of Neanderthal and Spy, a very decided step is made in the direction of the "missing link." [15] Quatrefages and Hamy, _Crania Ethnica_. But if we accept the only two specimens known of the type of Tertiary man, the skulls of Castelnedolo and Calaveras, which are supported by such extremely strong evidence, it would seem that as we recede in time, instead of getting nearer to the "missing link," we get further from it. This, and this alone, throws doubt on evidence which would otherwise seem to be irresistible, and without a greater number of well-authenticated confirmations we must be content to hold our judgment to a certain extent in suspense. This, however, it must be remarked, extends only to the type of man as shown by these two skulls, and does not at all affect the fact that man, of some type or other, did exist in the Pliocene and Miocene periods, which is established beyond reasonable doubt by the numerous instances in which chipped implements and cut bones have been found by experienced observers, and pronounced genuine by the highest authorities.