A more famous discovery in California was that of the "Calaveras skull" (pi. 1, jig. 34). It was taken front a mining-shaft one hundred and fifty feet deep in Calaveras county. The shaft passed through five beds of lava and volcanic tufa and four beds of auriferous gravel. The lower grayel-beds are considered as belonging to the Pliocene Epoch of the Tertiary, so that this skull, if originally from that deposit, carries the advent of man in North America far back of the age of the earliest Qua ternary in Europe. The skull was carefully examined by Professor Jef fries Wyman, who was inclined to admit its age. The craniological type was not markedly low (front view, fig-. 34). Later inquiry revealed the fact that the skull was not taken directly from the gravel, but was found at the bottom of the pit in a detached mass, which may have fallen front one of the upper gravel-beds. This circumstance has cast an air of doubt on its exact age. Nevertheless, there is no doubt that in repeated instances in California the bones of man have been found in intimate and original connection with those of the mastodon and the elephant, and at great depths—from one hundred to one hundred and fifty feet below the surface. Ilence we are forced to admit that tribes inhabited that coast at a time when these gigantic mammals roamed there in great herds.
_11exico and Central study has as vet touched Mexico and Central America but superficially, so it is not surprising that there are few reports of palreolithic discoveries in those regions. But that they also had human inhabitants at a very remote period is evidenced by several observations of the kind which have been published.
Thus, in ISS4 a remarkable find of human remains was made at a locality called Pefion de los Bailos, not far from the city of Mexico. Por tions of a human skeleton were discovered firmly imbedded in a calcareous tufa, all the surroundings of which indicated that it dated from the older Onaternary. The teeth were regular, and the cuspids had almost the same shape as the incisors, a peculiarity of many ancient Aztec remains.
The discovery of ancient human footprints in lava-covered mud on the shores of Lake Nicaragua by Dr. Earl Flint in 1882 seems also to prove a very early residence of man in that locality. But it must be acknow ledged that in a region of active volcanic agitation the course of nature is so abrupt, violent, and irregular that all ordinary measures of the age of deposits become inadequate.
OTher Ancien/ Defiosiis.—From time to time various other deposits containing human remains have been described, and asserted to show a geological antiquity for the human race in North America.
One of the earliest of these discoveries was by Dr. Koch of St. Louis, who in 1839 disinterred the skeleton of a mastodon from an ancient bog in Gasconade county, Missouri. In immediate connection with it he found flint arrow-heads and pieces of charcoal, as if the ancient inhabit ants had attacked and destroyed the animal when mired. His report was received with great incredulity, and has repeatedly been challenged, but there is nothing improbable in it. The mastodon was certainly alive in that locality long after man was resident there. The presence of stemmed and barbed arrow-heads, however, deprives the supposed event of any great antiquity, as stone implements of this character first came into use in the later portions of the Paleolithic Period.
We might also mention a fragment of a human pelvic bone found in a fresh-water loess formation near Natchez, and associated with the remains of the mastodon; various products of human industry with and below the bones of elephants in the salt-diggings at Petit Anse Island, Louisiana, and even fragments of pottery among the bones of the mastodon and other extinct quadrupeds on the banks of the Ashley River, South Carolina. These and others have not in all points received that confirmation which scientific students desire; but there is nothing so extraordinary in them as to call for unusual scepticism. There is not the slightest doubt that man was the contemporary of these animals, and it is quite possible that some of them survived after the period of polished stone implements and of pottery had well begun.
Crow Creek few instances have been adduced by sci entists which, it has been claimed, establish the presence of man west of the Rocky Mountains even in fall Tertiary times.
One such refers to a deposit of gravels in Wyoming Territory, on Crow Creek, a branch of the South Platte River. In these gravels Mr. E. L. Berthoud discovered in 1872 a number of roughly-chipped flint imple ments associated with irregular piles of pebbles. The materials employed were jasper, agate, granite, and basalt. The shape, the location, and the rough finish of the implements reminded the explorer of similar utensils from the gravel-beds of the Somme in France. The age of the deposit in which they occurred became, therefore, a question of the highest interest. Two species of shell obtained from the bed were decided by a competent conchologist to belong to species "certainly not later than the older Pliocene, or possibly Miocene." But this apparently satisfactory identification is largely undermined by another part of Mr. Berthoud's report, which describes these gravel-beds as formed by washings from a high dividing ridge to the north made up of miocene conglomerate. It seems probable, therefore, that these shells were washed down from the uplands, and that the gravel-beds are Quaternary.
Carson Footprints.—Another supposed evidence of man in the Mio cene acquired considerable celebrity a few years ago. This evidence was in the shape of his footprints distinctly impressed in considerable numbers on the sandstone of that age in Eagle Valley, near Carson, Nevada. The most careful observers agree that the resemblance of these marks to that of an Indian's moccasin when pressed upon a layer of thick mud by the weight of the body, is exceedingly close. To be sure, they seem too large, the footprints being nineteen inches long by six or seven inches broad. But this objection was in a measure removed by considering that in soft and slippery mud an exaggerated impression of the foot would be given, and still further, in the minds of many, by find ing a man now living on the Pacific coast whose shoes measure along the sole eighteen and a half inches. Nevertheless, a critical study of these footprints shows that the creature which left them threw its weight on the outer edge of the sole of the foot, and that it had a row of bristles along the edge of its sole—facts which leave scarcely a doubt that we have to do here, not with human footprints, but with those of a large species of sloth or some such edentate.