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Show 48 MR. W. P. PYCRAFT ON THE [May 2, vii. T he P elvic G irdle. Outside tlie Passerine series the pelvic girdle of the Eurylaemidae resembles most nearly that of the Capitonidae; from which, however, it may be distinguished by the fact that whereas in the Eurylaemidae the post-acetabular ilium is produced caudad into a spine, in the Capitonidae this backward extension is broad and bifurcate. Among the Passeres it approximates most closely perhaps to that of Chasmorhynchus. Cymbirhynchus only, among the Eurylsemidfe, appears to possess even a vestige of the pectineal process. In Calyptomena the pre-acetabular ilium is broad throughout its whole length, and sharply truncated anteriorly. The inferior border thereof is markedly sinuous. The pre-acetabulfe of the right and left sides are widely separated one from another ; and rise so as to lie nearly level with the ridge of the neural crest of the synsacrum, thus forming a large, open, canalis ileo-lumbalis. The post-acetabular region of the ilium is expanded to form a broad dorsal plane, and passing backwards terminates in a long spine, which, in Cymbirhynchus and Corydon, is closely applied to the free ends of the transverse processes of the post-synsacral caudal vertebra?. The ischium in Calyptomena is long, produced backwards considerably beyond the level of the post-acetabular region of the ilium, and terminates in a downwardly-directed liook-shaped process which fuses with the pubis. Cymbirhynchus differs but slightly from Calyptomena is this respect. In Corydon the ischium is shorter antero-posteriorly, and deeper, than in the two genera just described, and does not project beyond the level of the free end of the post-acetabular ilium. Further, the dorsal border of the pre-ilium is much cut away anteriorly so as to expose a great portion of the syn sacral neural crest. The ischio-pubic fissure is closed in all three genera here described ; the obturator foramen is shut off therefrom by a bony bar. Tlie pubis is long and straight, and projects beyond the level of the ischium, especially so in Calyptomena. The close approximation of the post-acetabular ilium to the transverse processes of the free caudal vertebrae is due to the shortness of the transverse processes of the synsacral vertebra? already referred to. The fovea lumbalis is small; and the fovea ischiadica and pudendalis are confluent. viii. T he P ectoral L imb. The pectoral limb of the genera here described presents no marked differences by which they can be distinguished one from another. It resembles that of the Coliidae and Capitonidae in that metacaipal II. sends backwards from its proximal end a small triangular bony spur (intermetacarpal process) to abut against |
