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Tr ansae tions . — Zoo logy . 



In the absence of illustrations the following keys may 

 assist in distinguishing between the genera : — 



Middle Cervical Vertebra. 



Neural ridges nearly parallel. 

 Neural ridges high 

 Neural ridges low. 



Transverse bar high ; ridges short 

 Transverse bar low ; ridges long 

 Neural ridges markedly converging. 

 Neural depressions* deep 

 Neural depressions shallow. 



Dorsal margin of post-axial surface of 

 centra less than two-thirds of the 

 ventral margin 

 Dorsal margin of post-axial surface of 

 centra more than two-thirds of the 

 ventral margin. 

 Centra elongated 

 Centra shorter 



Thoracic Vertebra. 



Anterior pneumatic foramen descending below 

 the rib-facet in No. 27. 



Posterior faces of the centra of Nos. 26 to 

 24 broad. 



Neural spines short, square 

 Neural spines short, compressed 

 Neural spines long, compressed 

 Posterior faces of the centra of Nos. 26 to 24 

 narrow 

 Anterior pneumatic foramen not descending 

 below rib-facet in No. 27. 



Post-zygapophyses form an acute angle 



with each other 

 Post zygapophyses form a right angle with 

 each other. 



No posterior pneumatic foramen 

 A posterior pneumatic foramen 



Pelvis. 

 Centra of ribless post-sacral vertebra (Nos. 35 to 

 37) forming a mass which is as broad as long, 

 and transversely ridged. Two pelvic fossse on 

 each side. . 

 Mass of ribless centra longitudinally keeled or 

 ridged : generally longer than broad. 

 Ilia diverge at an angle of about 65° 

 Ilia diverge at an angle of about 90° 

 Mass of ribless centra much longer than broad, 

 nearly smooth, or slightly ridged. 

 Lower surface of the centra rounded 

 Lower surface of the centra flat, with sharp 

 lateral margins. 



Posterior portion of ilium sharply ridged 



below 

 Posterior portion of ilium flat below . . 



Dinornis. 



Pachyornis, section A. 

 Pachyornis, section B. 



Euryapteryx. 



Meionornis. 



Megalapteryx. 

 Anomalopteryx. 



Dinornis. 



Megalapteryx. 



Meionornis. 



Euryapteryx. 



Anomalopteryx. 



Pachyornis, section A. 

 Pachyornis, section B. 



Dinornis. 



Meionornis. 

 Euryapteryx. 



Pachyornis. 



Anomalopteryx. 

 Megalapteryx. 



* The depressions at the pre-axial ends of the neural ridges. 



