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Show 1900.] HAIR-SLOPE IN CERTAIN MAMMALS. 683 and with great uniformity, in a raised ridge of hair. The " feathering " diverges on each side, that on the gluteal region merging easily into the general hair-stream of this part, and the stream which passes on to the thorax sweeps more widely forward and curves again to the ventral surface, uniting with the hair-stream of the thorax. This character in Horses is universal, and I have found it present, more or less marked, in 25 other forms of Ungulates (see Notes, p. 686). B. Post-humeral or axillary.-This whorl, with occasionally a " feathering " arising from it, lies in the hollow between the great mass of extensor muscles of the fore-limb and tbe muscles of the thorax. It has been found by me in 87 Horses out of a very large number examined. In two of these it was unilateral; and of these 87, 57 were cart-horses, though the proportion of cart-horses examined was very small. In regard to this fact, it may be noted that in cart-horses the action of the shoulder-joint preponderates considerably over that of the carpal and metacarpophalangeal joints. One special group of 2159 Horses examined gave 42 cases of this feature, or nearly 2 per cent. I would suggest that this is a specially interesting case of a new character, like the more stable inguinal and pectoral whorls, being developed before our eyes. This whorl has also been noted in 16 other forms of Ungulates. (See Notes, p. 686.) Fig. 2. View of Horse showing post-bumeral and inguinal whorls with feathering, arrows indicating directions of opposing muscles. C. Pectoral.-This whorl (see fig. 3, p. 684) with oval " feathering " is bilateral, and extends from a point about at the level of tbe olecranon process over the mass of the pectoral muscles in a |