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Show 480 MR. R. LYDEKKER ON A N E W MOA. [Nov. 3, have their ridges and extremities abraded, apparently indicating that they have lain exposed for a long period to the action of the weather on the surface of the ground. Unfortunately, there is no record of the locality where the specimens were obtained. There are, indeed, other bones in the collection belonging to the typical species of the genus Pachyornis, which is known only from tbe South Island, but since they are in a different mineralogical condition, and evidently from another locality, no inference can be drawn from them as to the present specimens. As there are many specimens in the British Museum from the North Island (and none from the South) in the same condition as the latter, it appears probable that these specimens may be also from the North Island. The proportions of the tibio-tarsus and tarso-metatarsus show that the affinities of this Moa are with the genera Anomalopteryx, Emeus, and Pachyornis, and that it is quite distinct from Dinornis, in which the tarso-metatarsus is long and slender, and the tibio-tarsus is long and straight. The tibio-tarsus (Plate XXXVIII. figs. 2, 2 a) has a length of 22 inches and a distal width of 2"9 inches. These dimensions are alone sufficient to distinguish this specimen from the corresponding bone of all the species of Anomalopteryx and Emeus. Tbus in Emeus crassus, which is the largest representative of either of those genera, the tibio-tarsus has a length of 20"4 inches and a distal width of 3*3 inches. The present tibio-tarsus is, however, at once distinguished from the corresponding bone of all the species of both those genera (with the exception of the small Anomalopteryx [?] geranoides, which probably indicates a distinct genus) by the outward curvature of the shaft and the marked inflection of its distal extremity. In these respects the tibio-tarsus before us resembles the corresponding bone of the type species of the genus Pachyornis, from which it is, however, readily distinguished by its more slender proportions. Thus in the typical P. elephantopus the tibio-tarsus has a length of 24 inches, with a distal width of 4*2 inches ; while in an unnamed form l which not improbably indicates a distinct species the two dimensions are 20 inches and 3"5 inches. These measurements indicate conclusively that the present tibio-tarsus (in which, as I have said, these dimensions are 22 inches and 2*9 inches) cannot be referred either to P. elephantopus or to the unnamed species. A comparison of the individual specimens would render this still more apparent, the present tibio-tarsus being a slender bone recalling the straight tibio-tarsus of Dinornis, while the corresponding bone of these species of Pachyornis is remarkable for its extremely stout and robust proportions. W e now come to the question whether the Moa represented by this slender type of inflected tibio-tarsus can be included in the genus Pachyornis ; but before deciding this we must examine the other bones. Firstly, with regard to the tarso-metatarsus, which is represented in Plate XXXVIII. fig. 3. Unfortunately the extremities of this 1 Cat. Foss. Birds Brit. Mus. p. 318. |