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Show 280 MR. W. P. PYC'RAFT ON THE [Mar. 17, v ii . T h e P e l v ic G ir d l e . The pelvic girdle of the Cuculiformes, though recalling in certain features that of the Coraciiformes, is yet quite distinct therefrom. Within the group it presents a comparatively wide range of form. Among the Cuculi, the least specialised pelves are those of the smaller forms, such as Cacomantis (text-fig. 45) and Chrysococcyx. In Cacomantis the preacetabular region of the ilia is separated by a low swollen ridge formed by the centra of the lumbar vertebrae. The dorsal border is nearly straight; the ventral, external, border is deeply emarginate ; the anterior border truncated and rounded, curving outwards to form a hook-shaped antero-ventral angle. The postacetabular region of the ilium has Text-fig. 45. Dorsal aspect of the pelvis of Cacomantis memlinus, X 5, showing the widely separated preacetabular ilia, and the broad dorsal plane of the postacetabular region. a broad dorsal plane which abuts against the long and slender transverse processes of the vertebra?. These last, by the way, are separated by a row of intertransverse sacral foramina, one on either side of the column. The dorsal plane of the postacetabular ilium is not produced outwards so as to overhang the ilio-ischiadic fissure, and its postero-external border is markedly depressed, not forming an upturned crest as in forms to be presently described. That portion of the ischium which, by its upturned growth, converts the obturator fissure into a foramen is very narrow; below and behind the foramen the ischium is produced |