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Show 886 SIR V. BROOKE ON THE [Nov. 19, (2) Two slender pointed bones, the rudiments of the second and fifth metacarpals (Plate LV. figs. 1, 2' and 5'), situated posterior to and one on each side of the distal extremity of the metacarpal cannon. These bones articulate with their respective phalanges, but are separated from the carpus by a wide interval. The proximal phalanx of these digits (Plate L V . fig. 1, p)'\s superior in size to the central and ungual phalanges. For these forms Professor Flower has kindly assisted me in finding convenient names. For the former, that in which the proximal (or near) extremities of the lateral metacarpals remain, I would propose the term Plesiometacarpal (nXnaioy, near, and peraxdpTrior, metacarpus); and the latter, that in which the distal (or more remote) extremity of these bones remains, I would designate Telemetacarpal (rrjXe, far, peraKcip-Kior, metacarpus). With the view of ascertaining whether the myology of the fore limbs of the Cervidae confirms or confutes the importance which I would assign to their osteological characters, I have been lately engaged in the examination of the muscles of the fore limbs of the Artiodactyles in general. M y materials have been, however, as yet far too meagre to justify m e in attaching any great weight to the characters afforded by myology; but I am encouraged in expecting that my observations may not be altogether unimportant, in which case I shall hope to lay them before the Society upon some future occasion. I will only here mention that in the telemetacarpal limb of the Common Roe, the phalanges of each lateral digit are supplied with two tendons from the extensor muscles of the forearm-a condition precisely similar to that which obtains in the tetradactyle Tragulus. On the other hand, in the plesiometacarpal limb of the Red Deer and Fallow Deer, the lateral phalanges are entirely without muscular attachment. In neither the Roe, Red Deer, or Fallow Deer are the lateral phalanges supplied with tendons from the flexors. A similar condition is seen in Tragulus, in which form the lateral phalanges are but slightly functional; but in the telemetacarpal limb of Moschus the lateral phalanges are (as in Sus) supplied with strong tendons from the flexor profundus digitorum. In Moschus, the lateral phalanges are highly functional. The special office performed by the lateral phalanges is the prevention of the animal slipping when rushing at speed down slopes or sinking in swampy ground ; and this function is effected without danger of the displacement of these delicate structures, by means of strong ligamentous bands developed in the aponeurosis surrounding them, which bind them firmly in their normal position. In the telemetacarpal limbs which I have examined, in addition to these bands, distinct round ligaments pass from the sides of the distal articular surface of the metapodium to the centre of the metacarpal splint on each side (Plate LV. fig. I, r-r), and aid in preventing its displacement upwards, upon undue pressure being applied from without. In the annexed list of all the known species of existing Deer, arranged according to their geographical distribution, the names of |
