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Show 1902.] OSTEOLOGY OF THE FALCONIFORMES. 305 Aquila, Thrasaetus, Haliaetus, Circaetus, for example, the post-ilia pass insensibly backward into the ischium, instead of abruptly. Text-fig. 37. Dorsal aspect of the Pelvis of Pandion haliaetus. As in the pelvis of Gathartes, the preacetabular ilia fail to rise above the neural spines of the vertebra?. A pair of canales ileo-lumbales are present, but most of the intertransverse sacral foramina have become filled up. The great breadth of the pelvis, as shown in text-fig. 36, p. 303, is caused by the unusual length of the sacral ribs and transverse processes. In the majority of Accipitres the pre- is longer, sometimes nearly twice as long, than the postacetabular ilium, which is markedly deflected. The ischium is generally truncated posteriorly, but in some, as in Thrasaetus and Aquila for example, the posterior end is hastate. The pubis is generally long and slender, and at the level of the end of the ischium turns abruptly inwards towards the middle line nearly meeting its fellow of the opposite side. In Thrasaetus, Lophaetus, Parabuteo, it is vestigial, only the proximal end remaining. This terminates immediately behind the obturator foramen, and serves to close it, often by fusion with the |