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Show 334 DR. ST. GEORGE MIVART ON THE SKELETON OF [Apr. 2, processes are relatively longer and more slender, notably that of the fourth true rib. The fifth thoracic rib is more slender, and is very slender in L. fiavopedliatus, in which it bears no uncinate process. It may bear a small and simple one in P. erithacus. The sixth thoracic or first floating rib is longer than the fifth true rib, and still more slender, and is more or less anchylosed to the sacrum. N o seventh thoracic or second floating rib is developed in L. fiavopedliatus, but m a y be present in P. erithacus. Then it is long, very slender, and anchyloses with the sacrum. The Sterncd Ribs. There are five sternal ribs (figs. 12 & 14, pp. 324,326) on each side which articulate dorsally with the respective apices of the thoracic ribs and ventrally with the sternum. The last three are expanded dorso-ventrally at their proximal ends. They are expanded transversely at their distal ends; each presenting there a surface some- Fig. 20. ,m do do Ventral aspect of sternum of Lorius fiavopalliatus. ca. Costal angle. do. Defect of ossification. h. Muscular impression. i. Intermuscular ridge. k. Keel. m. Manubrium. p. Lateral angle. |