[13] Since the above was written, Professor Marsh has described, in _The American Journal of Science_ for June, 1892, several more or less complete skeletons of Triassic Dinosaurs, lately found, and now in the Yale College Museum. This is an important discovery. [Illustration: Fig. 14.--Portion of a slab of New Red Sandstone, from Turner's Falls, Massachusetts, U.S., covered with numerous tracks, probably of Dinosaurs. This specimen is now in the Natural History Museum. The separate tracks are indicated by the numbers. (After Hitchcock.)] There is at South Kensington a fine series of these and other specimens of fossil footprints (Gallery No. XI., Wall-cases 8-10). The surface of one large slab in the geological collection is eight feet by six feet, and bears upwards of seventy distinct impressions disposed in several tracks, as shown in Fig. 14. The lines were added by Dr. Hitchcock, who has published full descriptions in order to show the direction and disposition of the tracks. [Illustration: Fig. 15.--Portion of a slab, with tracks. (After Hitchcock.)] In a presidential address to the Geological Society, Sir Charles Lyell, speaking of the Connecticut Sandstone and its impressions, said, "When I first examined these strata of slate and sandstone near Jersey City, in company with Mr. Redfield, I saw at once from the ripple-marked surface of the slabs, from the casts of cracks, the marks of rain-drops, and the embedded fragments of drift-wood, that these beds had been formed precisely under circumstances most favourable for the reception of impressions of the feet of animals walking between high and low water. In the prolongation of the same beds in the Valley of Connecticut, there have been found, according to Professor Hitchcock, the footprints of no less than thirty-two species of bipeds, and twelve of quadrupeds. They have been observed in more than twenty localities, which are scattered over an area of nearly eighty miles from north to south, in the States of Massachusetts and Connecticut. After visiting several of these places, I entertained no doubt that the sand and mud were deposited on an area which was slowly subsiding all the while, so that at some points a thickness of more than a thousand feet of superimposed strata had accumulated in very shallow water, the footprints being repeated at various intervals on the surface of the mud throughout the entire series of superimposed beds." When Sir Charles Lyell first examined this region in 1842, Professor Hitchcock had already seen two thousand impressions of feet!