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Show 4 70 DR. J. MURIE ON SAIGA TARTARICA. [June 9, 3. Bones of the Extremities. (A) Scapula and fore limbs.-Whilst the shoulder-blade shows no special specific or generic mark, it yet, I would say, is impressed more with Antilopine than Ovine form. This, I think, is owing to its somewhat greater length to breadth and upturned axillary border. Its long diameter is 7, and breadth at vertebral end 3 | inches. The supra- is about a third of the breadth of the infraspinous fossa; the spine has a concavity towards the latter; the acromion process is obsolete, a tubercle of bone alone representing it. There is a well-marked neck, flattish and widened by a flange of bone at the axillary border. The glenoid cavity is shallow, incised at the coracoid end, this process being short and broad. The tricipital border is thick, wide, and markedly grooved, and towards the vertebral end rises at a right angle to the plane of the infraspinous fossa in a prominent strong plate of bone for the attachment of the teres major muscle. The cartilage at the spiual end was semiossified in the male specimen. The shaft of the humerus is roundish, but with a tendency to posterior angularity. Head and neck relatively to the shaft are massive. The great tuberosity is very broad, strong, and thick, obliquely salient inwards. Tbe deltoid eminence and elevation for attachment of the teres major are each well developed. The bicipital groove is flattish and unusually broad. The articular capitulum is deflected posteriorly, its upper surface being moderately convex and broad ; the inferior extremity presents little or no difference from that of the Sheep. There is a moderately broad shaft to the radius, which has a slight bend forwards, and, as usual, is convex in front, but almost flattened behind. The stout olecranon rises 2 inches above the radius; and the shaft of the ulna is represented by a slender rod continued to the short styloid process, where it somewhat widens out. The carpal bones consist of the usual ruminant number, 6, viz. the scaphoid, semilunar, cuneiform, and pisiform in the first row, and os magnum (with united trapezoid) and unciform in the second. Proximately the scaphoid, lunar, and cuneiform are arranged in a close-fitting semilune, the pisiform bone being, as it were, accessory, placed posteriorly and comparatively free. The magnum and unciform form an inferior and reduced semilune, modelled accurately to the upper surface of the metacarpal pillar. A sufficient hollow is provided behind these bones for the tendons &c. to be bound firmly by transverse ridges of fascia, and enabling them to play with security during the frequent jerking movements of this part of the limb when in action. The scaphoid, of good size, has an upper deepish median hollow which lodges the greater part of the inner facet of the radius. The said hollow is somewhat laterally constricted, but posteriorly rises as a tuberosity. The underside of the scaphoid occupies more than the outer moiety of the connate os magnum and trapezoides. The uneven outer side of the bone rests in the corresponding rough concavity of the lunare. |