|Mean.| 15·1 | 2·88 | 2·9 | 126 × 91 | ·188 | ·730 | | | | | | | | | +-----+-------+----------+--------+----------+----------+-----------+ Comparison of the mean proportions given in the two Tables shows:-- (1) That the Perthi-Chwareu leg-bones are, on the whole, shorter, and absolutely smaller in all dimensions but one, viz. in the antero-posterior diameter of the shaft, which, notwithstanding the smaller size generally of the bones, is rather greater (that is to say, in the proportion of 129 to 126) than in the ordinary run of English _tibiæ_. (2) That their perimetral index is greater, showing that, in proportion to their length, the Welsh bones are somewhat thicker, or in the proportion of 211 to 188. (3) But the most marked difference is seen in the latitudinal index, which in the Perthi-Chwareu bones is ·611, and in those of the ordinary type ·730, varying in the former case from ·538 to ·700, and in the latter from ·642 to ·850; but the last is probably an exceptional case. In accordance with this, we find that the mean transverse diameter of the shaft at the point above indicated is greatly under the usual mark, viz. as 79 to 91. It is clear, therefore, that the Perthi-Chwareu _tibiæ_ are more compressed or flattened than the usual run of modern European _tibiæ_; in other words, they belong to the platycnemic type. As this is, I believe, the first instance in which the occurrence of _tibiæ_ of this peculiar conformation has been observed in this country, the circumstance is of some interest, especially with relation to the occurrence of priscan bones of the same type elsewhere. This peculiar conformation of the _tibia_, to which we gave the name of “platycnemic,” was, I believe, first noticed by Dr. Falconer and myself, in 1863, in the human remains procured by Captain Brome from the Genista Cave, on Windmill Hill, Gibraltar, of which an account will be found in the Transactions of the International Congress of Prehistoric Archæology for the year 1868 (p. 161); and about the same time, or in May 1864, M. Broca[109] independently observed the same condition in _tibiæ_ procured from the dolmen of Chamant (Oise), and afterwards in bones from the dolmen of Maintenon (Eure-et-Loire). Similar bones have since been noticed in other localities on the Continent, as, for instance, in the diluvium of Montmartre, by M. Eugène Bertrand. But that the peculiarity in question is not common in all the varieties of priscan man belonging to the reindeer period is shown by the fact that it has not been observed in any of the _tibiæ_ exhumed by M. Dupont in the Belgian caves.