OCR Text |
Show 126 DR. R. W. SHUFELDT ON THE [Feb. 3, Summary of the chief Osteologkal Characters of the North-American Pici. 1. Large, but simple-scrolled turbinals; there may be a free turbinal. 2. Bulging of the frontal region over the transverse cranio-facial line m a y (Picoides) or may not (Colaptes) exist. 3. Generally the external cranial vault is more or less dinted by the ends of the quills of the capital feathers. 4. The interorbital septum is sometimes entire and sometimes shows a fenestra. 5. Pars plana large, and often the os uncinatum is well-developed. 6. Lacrymal usually vestigial in character. 7. Quadrato-jugal aborted. 8. Tympanic bullae cowrie-shell shaped, and otherwise peculiar. 9. A large spur on the upper side of either pterygoid for muscular attachment. 10. A median, dagger-shaped vomer sometimes present but sometimes absent. 11. Maxillo-palatines rounded, laminar and very much aborted. 12. A more or less imperfect nasal septum usually present. 13. Vestigial basipterygoid processes are distinctly developed in some species. 14. A s ossification advances in the palatines it m a y be characterized as being " ragged" along the antero-mesial and antero-external margins of these bones. This often leaves little osseous islets not absorbed, a few of which may persist here and there throughout the life of the individual. 15. Either palatine is characterized by possessing an "interpala-tine spine " or process, and this m a y be continued forwards to fuse with the mesial border of the bone by its free tip. Either palatine also possesses a palatine spur, springing from the anterior point of the internal lamina of the bone and being directed forwards. It may also in some species pass on to fuse with the mesial edge of the palatine to which it belongs by its free end. The posteroexternal angle of a palatine is either truncated or shows various degrees of being bluntly rounded. 16. The mesopterygoid process of a pterygoid is not paddle-shaped, but long and narrowly pointed. 17. Distinct orbito-sphenoids exist in the nestling. 18. Mandible very strong, typically V-shaped in pattern ; sides deep ; symphysis varies in depth ; ramal vacuity absent, or minute if present, and never large. Posterior angular processes more or less truncated ; internal angular processes large. In some species the posterior third of the inferior ramal border somewhat tumefied and roughened. 19. Rudimentary cerato-hyals which early fuse together. 20. Uro-hyal absent. 21. Elongated thyro-hyal elements curl up over the cranium to a greater or less extent. They may pass round the right orbit. |