414? PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 20, 



nearly circular, very rough, with a deep and broad groove about 

 one-third above its inferior margin. 



in. lOths. 



Diameter of articulating surface 1 2 



Length of pedicle 9 



Length of whole rib 1 7 



Lateral expansions 2 1 



Of the lateral expansions one-third part is anterior and two -thirds 

 posterior. 



Dorsal and Lumbar'? vertebrce. — Thirty-four in number; the ma- 

 jority of them are now concealed by the sternal bones, which, to- 

 gether with the sterno-costal arcs, were removed for the purpose of 

 examining the number of vertebras, &c.: the sterno-costal arcs are 

 not restored to their natural position, but kept separate. 



The dorsal vertebras are not carinated upon the inferior plane of 

 the centrum, as are the cervical and caudal. The surface is smooth; 

 they are deeply concave on their inferior line; thus in the thirteenth 

 vertebra, the antero-posterior diameter being 2^^ inches, the con- 

 cavity is half an inch. 



Sacral and Caudal vertebrce. — Thirty-one in number. 



ft has been stated that the cervical vertebrae are carinated on their 

 inferior plane and that the ridge or carina does not exist on the dorsal 

 vertebrae. In the caudal vertebrae there are two strongly-marked 

 angulations or ridges, giving these vertebrae a remarkably distinct 

 character from those of the anterior portion of the spinal column. 



The haemapophyses partake of the general robust character of the 

 whole skeleton. 



The true ribs are large, several of them two feet in length, with 

 a diameter of \-^-q inch ; their exact measurements cannot be ob- 

 tained in consequence of the overlying of the shoulder and sternal 

 bones. 



Entosternum. — This bone is large, but much mutilated ; its lateral 

 length in a line with its anterior concavity was 16 inches ; its antero- 

 posterior length, taken at the widest part across its lateral expansion, 

 is Ty^o inches ; its anterior concavity Sy^ inches in depth. 



Sterno-costal arcs. — These have been removed en masse for the 

 purpose of exposing the dorsal vertebrse and ribs; they are now 

 placed separately in the same case (Plate XVIII. fig. 4). 



in. lOths. 



Length of the median piece 13 



Diameter in centre 1 



Coracoids. 



Antero-posterior dimensions 17 



Breadth from median line to the glenoid cavity 8 8 



Scapula and Clavicle. — These bones being anchylosed, form one 

 large triradiate bone. 



Its anterior expansion 7 



Its lateral expansion 6 



