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Show larg er and more massively constructed, the neural spine especially being much thicker. The posterior part of the pedicle of the arch is perforated by a channel which opens anteriorly into the groove for the second spinal nerve, and posteriorly on the hinder face of the base of the transverse process. This latter opening is present in the recent vertebra, but the passage from it seems to lead into the substance of the bone of the centrum. The posterior zygapophvses are considerably more massive in the fossil. The dimensions of the recent and fossil axes are as follows :- Fossil. Recent. 1 9 0 5 .] REMAINS OF THE MUSK-OX. 51 cm. cm. Width of anterior face of centrum ....... 11'8 l l 'O Height ,, ,, ,, ....... 5-4 4-9 Length from tip of odontoid to middle of posterior face of centrum ................ 7 5 (v4 Width of posterior face of centrum....... 7-() 6'2 Height ,, ,, ,, ....... 5-8 4-9 Length of ventral surface of centrum ... 6-2 5-4 A portion of a left ulna from Plumstead consists of the shaft only. As in the case of the axis, this bone is larger and stouter than that of the recent animal, with which it was compared as far as its incomplete condition allowed. It was probably three or four centimetres longer : the least width and circumference of the shaft are 4'5 cm. and 12-3 cm. respectively, as compared with 4 cm. and 10-8 cm. in the recent bone. Professor Boyd Dawkins gives the circumference of a radius measured by him as 4-4 in. (approximately 11 cm.). An imperfect femur, also wanting the extremities, was found in the same place. It seems to have been longer and at the same time more slender than in the recent animal. Its length from the tip of the lesser trochanter to the middle of the supra-condylar fossa is 18 cm. : the width and circumference of the shaft are 5' 1 and 11 cm. respectively. In the recent animal these measurements taken at corresponding points are :-length 17-3, width 34, circumference 11'7 cm. The most recent find of Musk-Ox remains consists of an incomplete skull of an old bull (text-fig. 14, p. 52): this specimen, which is much rolled and water-worn, was discovered by Mr. Wm. T. Rennie near the base of a bed of gravel about eleven feet thick, nexr Frampton-on-Severn, about five miles from Stonehouse, Gloucestershire. Both this specimen and a humerus of Bos pri-migenius from a few feet above it have been presented to the British Museum by the finder. The skull has lost the whole of the facial region in front of the orbits above and the cribriform plate below. Moreover, nearly all the prominent points are greatly abraded : thus the ends of the horns, the occipital condyles, and the mastoid region together with the paroccipital processes are wanting. The obliteration |