The number of skeletons of all ages, and of both sexes, buried in these caves was very considerable; and they had been placed on the old floor of occupation at successive times. In that of Rhosdigre the accumulation of charcoal, broken bones, and fragments of pottery below some of the human skeletons, proved that it had been used for a habitation before it was used for a burial-place. It is very probable that originally the head of a family, or a clan, or a tribe, was buried in his own cave-dwelling, and that it was afterwards used as a cemetery for his blood relations and followers. _The Neolithic Caves in the neighbourhood of Cefn, near St. Asaph._ The same class of remains, referable to the neolithic age, have been met with in the caves in the limestone cliffs of the beautiful valleys of the Clwyd and the Elwy, near St. Asaph. In the collection of fossil bones in the possession of Mrs. Williams Wynn, discovered in 1833, in a cave at Cefn, by Mr. Edward Lloyd,[98] is a human skull and lower jaw, along with platycnemic limb-bones. They were found mingled with the bones of goat, pig, fox, and badger, and cut antlers of the red-deer, inside the lower entrance of the cave, in which the extinct pleistocene animals were found in the valley of the Elwy. Four flint flakes also were discovered along with them. The skull in its general features strongly resembles those found in the group of caves at Perthi-Chwareu, and presents a cephalic index[99] of ·770, which comes within the limits of the extreme forms from that locality. Professor Busk, however, as will be seen in his account of this skull, because of its low altitudinal index--·702, as compared with ·710 of the lowest Perthi-Chwareu skull--is inclined to view it as of a different type. The conditions, on the other hand, under which it was found appear to me to be circumstantial evidence that the interment is of the same relative age as that of Perthi-Chwareu. Both were in caves: in both the remains of the same domestic and wild animals were found in the same fragmentary condition. Flint flakes also occurred in both; and what is more important, the platycnemic limb-bones in both imply a somewhat similar mode of life in the people to whom they belonged. This body of evidence, in favour of the interments having been made by the same race of men who lived some time in Denbighshire, seems to me of greater weight than that to the contrary afforded by the difference of ·008 in the altitudinal indices of the skulls. After a comparison of the carefully prepared measurements of the crania published in the “Crania Britannica” with those published elsewhere, I cannot resist the conviction, that if similar modes of life and of burial in Britain imply an identity of race, cranial variation within the limits of that race is by no means very small. Absolute purity of blood in an island so near the Continent as Britain cannot be looked for; and unity of type resulting from isolation from other races, such