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Show 1893.] BIRD-BONES FROM THE MIOCENE OF ISERE. 519 PHASIANUS ALTUS, Milne-Edwards. (Plate XLL figs. 5-8.) As already mentioned, Dr. Deperet has referred to this species certain remains from St. Alban, and four specimens in the present collection seem to fully justify this determination. The bones on which this species was originally founded were but very imperfect, and our knowledge of its osteology was advanced by those described by Dr. Deperet, which included the lower end of the tibia, the upper extremity of the tarso-metatarsus, a part of the upper end of the femur, and some fragments of the metacarpus. The specimens in the present collection comprise the proximal part of the left tarso-metatarsus (Plate X L L figs. 5, 5 a), the distal end of the left humerus (fig. 6), the entire left ulna (fig. 7), and the complete left metacarpus (fig. 8). From their all pertaining to the left side it seems not improbable that all the four are portions of a single bird. These bones agree with those previously described in indicating a bird of considerably larger size than the C o m m o n Pheasant, being in fact intermediate in size between that species and the Peacock. They also decisively confirm the reference of the species to the genus to which it is assigned1. For instance the intermetacarpal bar of the metacarpus (which of itself sufficiently indicates the gallinaceous nature of that bone) is far smaller than in Pavo, and comes nearest in this respect to Phasianus; while the proximal part of the tarso-metatarsus has the same narrow shape as in the latter, with a deeper groove and one more ridge on its posterior surface than in Pavo. Other characteristic features of Phasianus are the single and prominent tubercle for the insertion of the tibialis anticus, the opening of the two superior perforations on the same horizontal line, the large size of the tibial cups and the comparatively small tubercle between them, and also the single tube and two shallow grooves in the hypotarsus. The diameter of the proximal extremity of this specimen is 0,017 mm., against 0,016 m m . in the one described by Dr. Deperet; while both in his and the present specimen of the metacarpus the diameter of the proximal extremity is 0,015. Beyond stating that the length of the ulna is 0,094 mm., while the transverse diameter of the distal end of the humerus is 0,0205 mm., the other specimens do not call for further mention. PAL^ORTTX EDWARDSI, Deperet. (Plate XLL figs. 9, 10.) The Gallinaceous birds from the Upper Eocene of Paris and the Lower Miocene of the Allier described by M . Milne-Edwards under the name of Palceortyx are easily recognized, among other characteristics, by the large size of the tricipital fossa of the humerus, which extends for a considerable distance under the head. In this feature these birds resemble to a certain extent the living 1 I may mention that, as is frequently my custom, I determined the genus of these bones before referring to tbe description of the birds previously recorded from the formation whence they were obtained. 35* |