OCR Text |
Show *878.] CLASSIFICATION OF THE CERVIDAE. 891 bo compensate for the extra development of some other part; The transmission and fixation of such variations by heredity. (1) The gradual evolution of the antlers from very simple to more complex forms. The earliest Cervine animal of which we have any knowledge is Dremotherium from the early Miocene of Europe. This species was, so far as is at present knowii, without antlers. In the middle Miocene of France and Germany, and in a somewhat similar horizon in North America, the earliest antlered Deer as yet discovered have been found. These species, belonging to the very closely allied genera Dicrocerus and Cosoryx, possessed very short antlers* with a single tine projecting forwards ; in fact they closely resembled the antlers of the existing species of Furcifer (fig. 17, p. 923). From this period to recent times a gradual increase in the luxuriance of growth and diversity in the form of the antlers is evidenced even by the miserably imperfect materials as yet at the command of naturalists. Of this the following forms bear witness :- CERVUS MATHERONI, Gerv. Cervus matheroni, Gaudr. An. foss. Mont Le'b. p. 66, pl. 13. Horizon. Upper Miocene. CERVUS CUSANUS, Croiz. & Job. Cervus cusanus, Boyd Dawk. Quart. Journ. Geol. Soc. 1878, p. fig. 2. Horizon. Pliocene (Lower ?) CERVUS PERRIERI, Croiz. & Job. Cervus perrieri, Boyd Dawk. Quart. Journ. Geol. Soc. 1878, p. 488, figs. 3-5. Horizon. Pliocene. CERVUS CYLINDRICORNIS, Boyd Dawk. Vide loc. cit. p. 415, figs. 11, 12. Horizon. Upper Pliocene. CERVUS TETRACERUS, Boyd Dawk. loc. cit. p. 417, figs. 13-17. Horizon. Upper Pliocene. MEGACEROS HIBERNICUS. Horizon. Post-tertiary Deposits. CERVUS ELAPHUS. Horizon. Post-tertiary deposits, and existing epoch. I need hardly say that these species have no direct affinity to each other ; they are simply chosen as illustrating the general fact that the antlers of the Cervidae have gradually increased in complexity from the Upper Miocene period to recent times. It might at first sight appear as though the occurrence of existing species with very simple antlers militated against the more compre- |