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Show 342 DR. J. MURIE ON T H E [May 26, family by tbe Markoor (Capra megaceros,Hutton), that noble-looking Ilimalayan Goat, the elementary composition of the hair under the same microscopic power as the preceding may be thus defined. The entire thickness of the hair is less than in the Red Deer and greater than in Cuvier's Gazelle ; the cortical substance is relatively about equal in depth to the last and decidedly greater than in the former or in the Wapiti Deer. The medulla bears an increase of ratio with the Gazelle's, but a decrease compared with the other two forms. The cells are much smaller than in the Deer, though larger than in the Antelopes; and, as if manifesting closer affinities to the latter, besides their narrow transversely ovate character, they further simulate that type in their compression in the direction of the long axis of the hair-tube. Reverting to the hair of the Prongbuck, it thus becomes evident that it is widely dissimilar in its constituent elements to the Antelope and Goat families. In some respects it approaches nearer to the Deer tribe, though still far from akin. The closest alliance, as far as the hair is concerned, is towards Sheep, though it may be noted that in the marked denticulate condition of the medullary cells it is impressed with a character of its own. The form of the upper lip in the hollow-horned Ruminants Ogilby has assumed to be a guide of considerable importance, inasmuch as from it we can discriminate affinities of resemblance exercising influence, not only on the animal's habits and economy, but vesting the premaxillaries with special characters. The Prongbuck belongs to his section of browsers in having no mufflle, and a hairy nose of the ovine or antilopine type, as Gray duly appends to its generic characters. Concerning the horns, or rather the process whereby they are shed, Mr. Bartlett's and Dr. A. Canfield's observations are most satisfactory, and excellently related. I agree, however, with Drs. Gray and Sclater as to the nearer structural resemblance of the horns to those of the Bovidae than the Cervidae, notwithstanding their deciduous nature. Indeed, as Buffon* has asserted of the Ox, and Ogilbyt* of the Oryx, Singsing, and Leucoryx, these ruminants offer an example of corneous exfoliation. The last-mentioned authority expresses himself as having verified Buffon's observations, which the great French naturalist's contemporaries ridiculed. After comparing the structure of the young and mature bovine's horns, Ogilby says, " As in the case of the second dentition, the permanent organ is developed under, or rather within, the other, and, by its growth, gradually carries it upwards, and supports it like a sheath or scabbard. The young horn, thus severed from the vessels which formerly supplied it with nutriment, dries up, bursts, from the expansion of the permanent horn within it, and exfoliates in large irregular stripes, leaving the latter with the finely polished surface and solid, sharp, attenuated points which distinguish them. As far as m y observations enable me to judge, this exfoliation takes place only once during the life of the animal, and that at the period of adolescence, immediately before the appearance of the first annulus." * Hist, Nat. t. iv. p. 459. t Trans. Zool. Soc. vol. iii. p. 53. |