OCR Text |
Show 1867.] PROF. HUXLEY ON THE CLASSIFICATION OF BIRDS. 421 4. The prefrontal processes are little ossified. 5. The bodies of the proper sacral vertebrae do not unite with the pubes or ischia; and the centra of the sacral vertebrae, which ossify late, are extremely elongated and slender. 6. The short sternum narrows posteriorly, and presents a notch in the middle of its posterior edge. 7. The length of the humerus exceeds the distance between the shoulder-girdle and the ilium, and is of course greatly longer than the scapula. The manus has the same conformation as that of Struthio. Fig. 2. Under view of tbe skull of Bhea americana. Pmx. Tbe prasmaxillce. B. The rostrum. Mxp. The maxillo-palatine. Vo. The vomer. Pl, The palatine. Pt. The pterygoid. * The basipterygoid process of the sphenoid. |