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Show 1903.] OSTEOLOGY OF THE CUCULIFORMES. 289 d. Beak not exceeding the cranium in length, of medium size, and with a more or less strongly arched culmen. ■e'. Descending process of lachrymal vestigial or wanting; temporal fossae meeting to form a sagittal crest; nostrils more or less markedly reni form, being formed like those of Rhinococcyx by the confluence of the narial aperture with a superior fenestra. c " . Descending process of lachrymal in form of delicate incurved style. a'". Sagittal crest reduced to a mere line.......................... Rhopodytes. b "'. Sagittal crest broad .......................................................... Zanclostomus. d ". Descending process of lachrymal reduced to a stump. Piaya. e ". Descending process of lachrymal wanting; antorbital plate slightly inflated ...................................................................................... Taccocoua. f'. Descending process of lachrymal moderately strong, bent outwards and backwards upon the supraorbital portion; temporal fossae meeting to form a broad sagittal crest. f " . Horizontal process of lachrymal longer than descending; pterygoid with dorsal keel; interorbital fenestra large .......................... Guira. g"'. Horizontal process of lachrymal not exceeding descending process, and having free orbital border sharply truncated; interorbital fenestra small. Eudynamys. g'. Descending process of lachrymal slender ; temporal fossa; meeting to form a broad sagittal crest; interorbital fenestra very large ... Centropus. h'. Temporal fossae confined to lateral aspect of skull. h". Lachrymal moderately large and not distinctly divided into supraorbital and descending processes; antorbital plate spongy; interorbital fenestra large ; maxillo-palatines not meeting in middle line, but palate edged by nasal septum ............................................................................. Coua. i" . Lachrymal moderately large, with slender descending process; nostrils cricular, just above base of tomium ............................... Coccystes. j " . Lachrymal vestigial; mandible with broad fiange at gape. c '". Temporal fossae present...................................................... Cuculus. d' " . Temporal fossae obsolete ................................................. Cacomantis. B . V e r t e b r a e 1. All the presynsacral vertebra; are free and heterocoelous; neural arch of atlas broad; hypapophyses blade-shaped, not extending beyond 2nd thoracic vertebra. Axis vertebra not conspicuously shortened antero-posteriorly, and not having conspicuously upturned hyperapophyses. A. Lateral borders of thoracic vertebrae terminating in a sharp backwardly directed spike...................................................................................................................... M u so ph a g i . B. Lateral borders of thoracic vertebrae not produced into spikes. C u c u li. 0 . P e c t o r a l G ir d l e a n d S t e r n u m . Coracoid with a well-developed procoracoid; clefts of the posterior notches of sternum never extending as far forwards as the level of the articulation of the ribs; furcula large. A. Procoracoid fused with acrocoracoid; furcula with a well-marked facet for articulation with the fused pro- and acrocoracoids; anterior border of carina sterni continued forwards to level of spina externa................. M u so p h a g i. B. Procoracoid not fused with acrocoracoid; furcula without articular facet for acrocoracoid; anterior border of carina sterna not continued forwards as far as free end of spina externa.................................................................... C u c u li . l The presynsacral vertebral of the Cuculiformes are scarcely to be distinguished from those of the Coraciince and Leptosomince. 19* |
