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Show 520 MR. R. LYDEKKER O N S O M E [June 6, Ammoperdix, Ortyx, and Coturnix, while they are totally different from Caccabis, Perdix, Phasianus, and most other members of the group. Probably the extinct Paloeoperdix, of the Sansan beds, Had a similar type of humerus, but the tarso-metatarsus is of a less flattened type. To the genus Palceortyx, Dr. Deperet has referred two imperfect humeri from Grive-St.-Alban, with which a complete specimen in the present collection agrees ; and as the associated specimens of the tarso-metatarsus appear to present the characters distinctive of that genus, I am disposed to accept his determination. The right humerus (represented in figs. 9,9« of Plate XLL)agrees precisely with the distal half of the corresponding bone figured by Dr. Deperet in pi. xiii. fig. 51 of vol. iv. of the Arch. Mus. Lyon, as one of the types of Palceortyx edwardsi; whde its proximal portion appears to correspond with that portion of another right humerus depicted in fig. 52 of the above-cited plate. In total length the humerus here figured measures 0,055 mm., or somewhat more than the corresponding bone of P. blanchardi, Milne- Edwards, from the Allier Miocene, in which the length is 0,047. According to Dr. Deperet the humerus of P. edwardsi differs from that of the last-named species not only in its superior size, but likewise in the absence of a distinct prominence on the outer side of the head. Compared with the corresponding bones of Ammoperdix and Ortyx, the present specimen, although much larger, is generally very similar, although there are certain differences which are evidently of generic value. The large size of the tricipital fossa differentiates the specimen from the existing Oriental Cryptonyx, and the extinct Palceocryptonyx from the Pliocene of Roussillon \ The right tarso-metatarsus (represented in fig. 10), of which the proximal extremity is imperfect, is evidently that of a partridgelike gallinaceous bird, and as it agrees approximately in relative size with the humerus, it may be tentatively assigned to the same distinctive species. Since it appears to present all the characters of Palceortyx rather than of Palceoperdix2, it confirms Dr. Deperet's reference of the species under consideration to the former rather than to the latter genus. PALCEORTYX MAXIMA, n.sp. (Plate XLL fig. 11.) The slightly imperfect right coracoid of a gallinaceous bird (represented in fig. 11), being of too large dimensions to have belonged to the same species as the humerus above mentioned3, while it agrees in all essential characters with the corresponding bone of Palceortyx, Ammoperdix, and Ortyx, may be taken to indicate a second species of tbe first-named genus, distinguished from all the others by its superior size. The length of this coracoid 1 Deperet, Comptes Rendus, vol. cxiv. p. 691 (1892). 2 See Cat. Foss. Birds Brit. Mus. p. 137. 3 In P. gallica, of which the humerus measures 0,042, or 0,005 less than the corresponding bone of P. blanchardi, the length of tbe assigned coracoid is only 0,025. |