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Show 1893.] BIRD-BONES FROM THE MIOCENE OF ISERE. 521 is upwards of 0,050 mm.; and this must for the present serve as the distinctive feature of this species. PALCEORTYX GRIVENSIS, n. sp. (Plate XLL fig. 12.) The right humerus (represented in fig. 12) indicates a species of the size of the Common Quail, and somewhat inferior in this respect to P. brevipes, which is the smallest of the Allier representatives of the genus. Thus, whereas in the present specimen the length is 0,0337 mm., in the corresponding bone of P. brevipes it is 0,0357 m m . On account of this inferiority of size, coupled with its much higher geological horizon, I am disposed to regard the present specimen as indicating a distinct species, which I assign to Palceortyx, with the name of P. grivensis. Compared with the nearly equal-sized humerus of Coturnix, this specimen exhibits very clearly the distinctive features between tbe two genera. Thus whereas in the Quail the subtrochanteric fossa is much larger than the shallow tricipital fossa, and extends beneath it, in Palceortyx the latter is much the larger of the two, and is of such a depth as to prevent the former from extending beneath it towards the outer side of the bone. PALCEORTYX, sp. inc. (Plate XLL fig. 13.) Seeing that in the Common Quail the humerus is of almost exactly the same length as the corresponding bone of P. grivensis, while the tarso-metatarsus measures only 0,027 m m . in length, it would seem impossible that the tarso-metatarsus now exhibited (see fig. 13), of which the length is 0,032 mm., can belong to the species last named. I accordingly regard it as probably indicating yet another species of the genus from La Grive, nearly of the same size as P. brevipes of Allier, but to which I do not consider it advisable to assign a distinct name. In its comparative flatness, as well as in the straightness of the hypotarsus and the depth of the external posterior groove, this bone exhibits all the features characteristic of Palceortyx as distinct from Palaioperdix. TOTANUS MAJORI, n. sp. (Plate XLL fig. 14.) From the presence of a distinct triangular ectepicondylar process, the small left humerus (represented in fig. 14) is clearly referable to the Gavise, Limicolae, or Tubinares. From the corresponding bone of the more typical Laridce it is readily distinguished by the smaller size of the tricipital fossa : while it differs from that of Sterna in the larger size of the ectepicondylar process. Compared with a skeleton of the Yellow-footed Sandpiper (Totanus flavipes), it is found to agree so closely with the humerus that there can be little hesitation in referring it to a member of the same genus. The total length is 0,037 mm., or about one-fourth less than that of the corresponding bone of the species above-named. A small species of Totanus from the Allier Miocene has been named T. lartetianus by Milne-Edwards ; but as the higher geological |