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Show 1902.] OF HORNS A N D ANTLERS. 207 " Horns"), an arrangement which we find adopted by Leche (op. cit. p. 980):- Os cornu absent-Integument unaltered the unpaired boss of the Giraffe. "Integument unaltered, os cornu persisting.. .paired horns of Giraffe. Integument thin, short-haired, os cornu cadue l Antler sensu Os cornu present strictiori-Subuli. [integument cornined { * " * * ^ f ^ ^ S . Leaving aside the erroneous statement that the median " horn" of the Giraffe possesses no separate bone-core or os cornu, but only a frontal boss, this arrangement looks much better than what it is intended to convey. In fact it represents exactly the phyletic stages which I shall endeavour to prove as correct. But Brandt says explicitly that the antler represents a higher, physiologically more complicated, differentiated stage of the bovine armament. In this respect he agrees with Rutimeyer, who considered the Cervidae as the " unfertigste und neueste" of all Ruminants. Moreover, Brandt suggests the following evolutionary stages: First, epidermal horns (analogous to those of Rhinoceros) ; secondly, the acquisition of frontal pedicles; thirdly, an os cornu and an antler. Lastly, the same author doubts the correctness of Riitimeyer's reasonable view that the Antilocaprine armaments are intermediate between those of Bovinae and Oervinae. Gegenbaur (1898), ignoring the os cornu altogether (op. cit, p. 106-107), misses the proper connexion which exists between horns and antlers. His remarks are not so precise and lucid as they might be, and there is not a word about the most suggestive preformation in a partly cartilaginous matrix. Nitsche (1898) has tried to give a coherent account of the whole question, but he does not seem to have made any other than macroscopic examinations. Starting with well-ascertained instances, observed in the Stag and Roe, where lesion of the side of an otherwise normal pedicle has caused the growth of extra antlers, he concludes that these cannot be anything but out-o- rowths or exostoses of the frontal bone. Consequently, he argues, such extra antlers cannot be homologous with normal antlers if such are dermal bones; i. e., according to his unfortunate definition, bones which are developed within the skin alone and without connexion with the skeleton. He then refers to the mode of growth of the first knobs and prickets of the young Roe, that there is no difference in structure and development between pedicle and pricket, anyhow that both are one and the same apophysis, while the separate existence of the os cornu in the Bovidae shows that their bone-core is an epiphysis. He then logically opposes the two organs to each other. Moreover, he looks upon the armaments of the Giraffe as exquisite types of cutis-ossification, in fact, as examples of free dermal bones, since they develop 1 Obviously a misprint of Brandt and Leche for caducum. |