170 



PEOFESSOE OWEN ON THE GENUS DINOKNIS. 



TWENTY-SECOND TERTEBEA (' 7th dorsal,' | nat. size). 

 Pig. 33. Fig. 34. 



Aspects. 

 Fig. 33, lateral ; 34, postaxial. 



Struthio. Rudiments may be indicated by the letters hy in Mivart's fig. 54 ; but they 

 are not noticed in the text. In the transverse direction the haemal surface of the 

 centrum is convex, as in StnifJtio. 



The preaxial surface in Ditwrnis is subquadrate, through the production of its 

 inferior angles, which, like the upper ones, are rounded off. Its transverse conca\dty 

 is less than in the sixth dorsal : it is relatively larger in proportion to the centrum than 



