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Show 1870] ANATOMY OF THE PRONGBUCK. 363 B. The Extremities. (a) Anterior limb.-Little deviation in the form of the scapula from that of ordinary ruminants is perceptible; it is of a long isosceles triangular shape, with a flat smooth blade, short neck, and well-developed spine (mesoscapula of Parker) an inch high at the middle. A tuberous but compressed coracoid process barely projects beyond the deeply scooped glenoid cup ; but no acromion extension is definable as obtains in Bovidae. The spine is situated anteriorly to the mesial line, so that the suprascapular is one-third less in width than the infrascapular fossa. The axillary border does not present a gutter and slope into the subscapular facies as is the rule in Artiodactyla, but, instead, forms a flat flange or shelf of bone | an inch broad at right angles from it, and whereon the teres major muscle arises. The bone of the scapula is 7\ inches in long diameter, and 4 inches broad at the vertebral border; a semiossified cartilage (Parker's suprascapular segment) extends 1 \ inch beyond. The humerus is shorter than the scapula by 0*3 inch. It has a moderately stout smoothish shaft, the upper half of which on cross-section would yield an antero-posterior subelliptical circumference, but its lower half a transverse one. A depressed articular semilunar head diverges backwards at almost right angles to the shaft's axis. The large inflated inner tuberosity, like the head, is flattish atop ; the bicipital groove is broad, elevated rather than depressed, with a wide excavation to its inner side for the insertion of the subscapularis. The outer tuberosity, ruminant-like, is a massive three-sided eminence raised £ an inch higher than the capitulum ; and it partially overarches the bicipital groove, though not at all so sharply in-turned as in the Mazama (Aploceros americanus). A smooth broadish boss marks the place of insertion for the supraspinatus muscle ; and an oblique deltoid ridge is amply represented. A minute nutritious foramen enters on the outside of the shaft at the commencement of its lower third. Laying the radius of the Prongbuck (which measured 7*8 inches long) side by side with that of a Fallow Deer of equivalent length, I observed the former had a narrower rounder shaft, and this gave to its proximal and distal extremities a more expanded character. The less convex but broader shaft of the Dama implied greater strength throughout. The shaft of the ulna is adnate to the above, it being a thin delicate bony splint, complete, however, from above downwards, and terminating in a well-developed trihedral styloid process. The olecranon is of good size. The entire ulnar bone measures 9g inches. From the limb-bones having been wired together in position before I had access to the skeleton, I was unable to compare the individual carpal and tarsal bones with those of other forms. The number, however, appears to agree with the typical ruminants and not with the aberrant Giraffe and Camel-there being in the carpus a scaphoid, lunare, cuneiform, and pisiform in the proximal row, and a trapezoides and os magnum in the distal one. |