430 



ME. ST. GEOEaE MIVAET ON THE 



The Fiftt-secojs'd Vertebka. 

 This vertebra closely resembles its serial predecessor, but is smaller in size (fig. 66). 



THE FIFTT-SECOKD, oe SIXTH CAUDAL VEETEBEA (natural size). 



Fig. 66. 



Fig. 66, preaxial aspect. Letters as before. 



The Fifty-third Vertebra. 

 Here the transverse processes project more postaxiad and ventrad, and the diapo- 

 physial part has greatly decreased relatively to the parapophysis. The spinous process 

 shows a more or less marked tendency to become trifid transversely at its apex. 



The Fifty-fourth Vertebra. 



This vertebra (fig. 67) is much smaller than its predecessor. The transverse pro- 

 cesses are very much smaller, but the apex of the neural spine is very distinctly trifid 

 transversely. 



The preaxial surface of the centrum is decidedly concave, as in all the vertebrae since 

 the fiftieth. 



THE FIFTY-FOUETH, oe 



EIGHTH CAUDAL VEETEBEA 



(natural size). 



Fig. 67. 



THE FIFTY-FIFTH and FIFTY-SIXTH, ok 

 NINTH a:sD TENTH CAUDAL YERTEBE.E 

 (natural size). 



Fig. 68. Fig. 69. 



Fig. 67, preaxial aspect (letters as before) ; 68, preaxial aspect of ninth caudal vertebra ; ^^s^ neural spine of 

 tenth caudal vertebra ; 69, lateral aspect ; d, osseous bridge connecting the portions. 



The Fifty-fifth Vertebra. 

 This vertebra is devoid of transverse processes ; or there are at most but minute faint 



