PHYLOGENY OF THE PALZOGNATHZ AND NEOGNATH, 
: i) 
“I 
Or 
Key to the Species. 
SrRurHio. 
a. Middle region of anterior border straight or slightly arched; length of 
coracoid groove greater than distance between articulations of sternal 
ribs 1-5. 
a’. Posterior lateral processes long and spatulate, with an extensively ossified 
metasternal region between the posterior lateral processes . . . . . S.molybdophanes. 
6’. Posterior lateral processes moderately long; ossified metasternal “us 
between posterior lateral processes small . . . . s . S. camelus. 
6. Middle region of anterior border of sternum sinuous ; iiosterion lateral pro- 
cesses not spatulate; no projecting metasternal region between the 
posterior lateral processes; length of coracoid groove less than the 
distance between the articulations of sternal ribs 1-5. 
c’. Width between the free end of the anterior lateral processes much greater 
than the width across their bases . . . . . 2 . 8S. meridionalis. 
d’. Width across free end of posterior lateral processes oe: ay to ‘the 
Wadthijacross them bases) <9 6.) = 6% mos < fe <= os a) ol S.eSinads: 
Ruea. 
a. Anterior border of sternum between the coracoid grooves slightly excavated ; 
width between right and left coracoid grooves greater than length of 
articular surface for coracoid ; articular surfaces for sternal ribs 3 . . . R&R. americana. 
6. Outer border of sternum between the coracoid grooves deeply excavated ; 
width between right and left coracoid grooves equal to or less than length of 
articular surface for coracoid ; articular surfaces for sternal ribs 4 . . . A. macrorhyncha. 
Dromazus. 
a. Length 64 in. Coracoid grooves distinct and the sternal protuberance but 
slightly developed . . . ..- - r . D.nove-hollandie. 
b. Length not exceeding 3% in.; coracoid grooves stibalekes fhe Saitealh os of 
right side only represented ; sternal protuberance conspicuous. . . . . Dz. ater. 
CasvaRius. 
A. With a pair of low, median, keel-like ridges lying immediately behind a line 
drawn across the sternum immediately behind the coracoid grooves, without 
median pneumatic cavity between the coracoid grooves . . . . . . C.unappendiculatus, 
B. Without paired median ridges; with large pneumatic cavity between the 
coracoid grooves. 
a. Coracoid grooves deep, the lower lip strongly marked when seen from 
above; pneumatic cavity very large, extending backwards into a low 
swollen protuberance lying in the middle line of the sternum between 
the coracoid grooves, 
