. Contributions to the anatomy of birds . e these combined bones inclose; the profundityof the pelvic basin. This is very much enhanced by broad reduplica-tures of the ilia and ischiabehind, and a generalthough even constriction ofa prominent rounded borderor rather ridge that extendsfrom the fourth diapophysialabutment of the vertebraagainst the ilia on either sideto the outer angles of the %ischia. Withi n, too, we oftenfind about and at the baseof these iliac fossae aperturesfor the entrance of air intothese bones; such pneumaticforamina are also seen be-yond the os x>ubis and belowthe c
. Contributions to the anatomy of birds . e these combined bones inclose; the profundityof the pelvic basin. This is very much enhanced by broad reduplica-tures of the ilia and ischiabehind, and a generalthough even constriction ofa prominent rounded borderor rather ridge that extendsfrom the fourth diapophysialabutment of the vertebraagainst the ilia on either sideto the outer angles of the %ischia. Withi n, too, we oftenfind about and at the baseof these iliac fossae aperturesfor the entrance of air intothese bones; such pneumaticforamina are also seen be-yond the os x>ubis and belowthe cotylis on either aspect. The pubic extremitiesnever meet behind, thoughin many species they arevery long and usually takethe curve given them by theischia just before leavingthese bones. Their distalextremities are flattened inCcntrocercus and generally more expanded than among the other varie-ties. The pelvis of Cupidonia is so different from the general descriptionwe have just given, that the author feels justified in giving his reader. Ortyx virginiana. 694 GEOLOGICAL SURVEY OF THE TERRITORIES. two additional figures, that present superior and lateral views of thebone in this bird; in comparing it with other figures given one cannotavoid being struck with these marked departures from the common is one other Grouse that affects this style of pelvis, and that isPedioecetes, and the attempt is not a bad one. The principal pointswherein the Sharp-tailed Grouse has failed to make a perfect imitationof the unique pelvis of his ideal are, the ilia have failed to produce suchponderous overhanging lateral flaps, that nearly shut out from view theischiadic foramen on either side. Again, these bones in Pediwcetes meetthe sacral vertebra? for their entire length internally; and in this bird,too, the pubic elements often unite all along the inferior borders of theischia. This does not occur in the Pinnated Grouse; otherwise thebones are very similar and marked exceptions to th
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectbirds, bookyear1882
