42 ME. ST. GEORGE MIVAilT ON THE 



THE AXIAL SKELETON OF DINOENIS. 



The osteology of Binornis has been in great part admirably described in the different 

 memoirs of Professor Owen in the ' Transactions ' of the Zoological Society (see vol. iii. 

 plate 19. figs. 1, 2, 3, plates 20 & 20 a. fig. 1, also plate 43. figs. 1, 2, 3 ; vol. iv. 

 p. 17 and plate 4. figs. 1-4, p. 159 and plate 47; and vol. vii. p. 115, plates 7, 8, 9). 

 Nevertheless it is not yet possible to give a complete description of its axial skeleton, 

 although the magnificent specimen of B. didiformis above referred to affords an 

 extensive amount of information on the subject. 



There appear to be fifteen cervical vertebrae and probably three cervico-dorsal, three 

 dorsal, and two dorso-lumbar vertebrae. There are also some eight or nine lumbar and 

 lumbo-sacral vertebrae, and three sacral ; but the number of caudal vertebrae does not 

 appear. 



THE \^RTEBR^. 



The cervical vertebrae in size and proportion of parts present a close general resem- 

 blance to those of Bromceus and Casuarius; but the fossEe postaxiad to the neui-al spines 

 appear to have been yet larger. The neui-al spine of the axis is lofty ; and those of the 

 fourth, fifth, sixth, and seventh cervical vertebrae are so grooved axially that they bifur- 

 cate laterally. The hyperapophyses of the axis are about as large as those of Bromceus 

 and Casuarius. 



Catapophyses appear already at the fourth vertebra, and continue on till, in the last 

 cervical, they are replaced by a median hypapophysis. The cervical styloid ribs were 

 most probably developed much as they are in Casuarius. 



The dorsal and lumbar vertebrae evidently had not equally elongated and much 

 axially extended neural spines, as in Apteryx, but probably about as developed as in 

 Bromceus and Casuarius. 



The Imnhar and lumbosacral vertebrae are broad ; and the more postaxial of them 

 (the lumbo-sacral) are devoid of transverse processes. The absence of these, occasions 

 the presence of two large crescentic fossae in the pelvis, one being internal to each 

 acetabulum. 



The sacral vertebrae send transverse processes to abut against the postacetabular part 

 of the ilium as usual ; but they are not sharply differentiated from the more postaxial 

 vertebrae as they are in Apteryx and Struthio. 



The sacro-caudal vertebrae are more dorsally situated with respect to the pelvis, as 

 regards the acetabula, than in any of the Struthionidse except Shea and Apteryx, and 

 closely resemble those of the last-named genus in this point, though they differ from 

 them in not being ventrad to the postaxial portions of the ilia. These vertebrae send 

 out transverse processes like those of the sacral vertebrae, and are thus hardly to be 



