OCR Text |
Show 1891.] OSTEOLOGY OF THE UNITED STATES COLUMBID.E. 195 types, such as have been described by the Newtons, by the Parkers, by Furbringer, and by many others \ So far as I have examined them, then, I find the Pigeons of this country to be :- 1. Completely schizognathous birds ; and with elongated narial apertures in the skull, which are not separated by an osseous septum nasi. 2. A large lacrymal bone is present, which fuses extensively with the pars plana, thus forming an unbroken plate. 3. With large vacuities in the anterior wall of the brain-case, the lower one of which merges with a big one in the interorbital septum. 4. Zygoma very slender. 5. Basipterygoid processes present, which may (in all save Ectopistes ?) or may not articulate with the short pterygoids ; the latter not in contact in the middle line anteriorly. 6. Palatines very slender, with their laminae somewhat reduced, and with their postero-external angles completely rounded off. 7. Maxillo-palatines antero-posteriorly elongated, internally spongy, and fused with the prepalatines, the maxillary, and the premaxillary. 8. The premaxillary process of the nasal bone carried far forwards, beneath the osseous culmen. 9. Sphenoidal rostrum sharp in front, thick and rounded behind. " 10. Vomer may or may not be present (?). Huxley figures the palate of Columba palumbus, and says " the vomer is very slender" (P. Z. S. 1867, p. 434) ; Parker says the Pigeons are without a vomer. 11. Quadrates typically ornithic, and with two transversely disposed facettes for articulation with mandible. 12. Mandible V-shaped, its symphysis short and feeble ; arti-culatory ends transversely truncated posteriorly, from above, downwards and forwards; ramal vacuity may (Ectopistes) or may not (Stamcenas) be present. 13. Eighteen (Ectopistes) or nineteen (Stamcenas) vertebrae in the spinal column between the skull and pelvis. Three leading dorsal vertebrae fuse together to form one bone (Ectopistes), and with it may fuse the ultimate cervical (Melopelia). Five (Stamcenas) or six (Ectopistes) free caudal vertebrae. A good-sized pygostyle present. Pelvis broad and shallow ; no prepubic spine present. 14. Os furcula U-shaped; without hypocleidium, and very slender. 1 To the U.S. National Museum, and to Mr. F. A. Lucas of that Institution, I a m indebted for the use of a skeleton of Ectopistes and one of Columbigallina passerina ; one of the assistants also, Mr. Schollick, has presented m e with a skeleton of the domesticated Pigeon known by the name of the " Archangel." Mr. J. S. Singley of Giddings, Texas, has likewise forwarded m e several valuable specimens.' M y private cabinet also contains numerous skeletons of our various species of Columbidce. 13* |