184 



933. The caudal vertebrae of the same Trionyx. 



They are twenty in number : the short pleurapophyses are anchylosed, forming apparently 

 long transverse processes, which gradually subside in the last six vertebrae : the zygapophyses 

 are developed as far as the sixteenth ; the bodies are all concave before and convex behind. 



934. The two episternals of the same Trionyx. 



935. The right hyosternal and hyposternal of the same Trionyx. 



936. The left hyosternal and hyposternal of the same Trionyx. 



937. The two xiphisternals of the same Trionyx. 



938. The entosternal of the same Trionyx. 



939. The right scapula, acromion, and coracoid of the same Trionyx. 



940. The left scapula, acromion, and coracoid of the same Trionyx. 



The acromion is an exogenous process of the scapula, which, as in other Chelonians, it 

 almost equals in length. The suture between the scapula and coracoid remains : the cora- 

 coid has a ridge along one surface, and being the most expanded bone of the three, much 

 resembles in shape the scapula of a ruminant quadruped. 



941. The pelvic arch of the same Trionyx. 



The sutures between the ilium, ischium and pubis are persistent. The ischium and pubis 

 join each other only at the acetabula and not at the median symphysis, as in the Land Tor- 

 toises. The foramina thyroidea are accordingly blended together to form one large, central, 

 oval vacuity. 



942. The right humerus of the same Trionyx. 



943. The left humerus of the same Trionyx. 



The bone is perforated from before backwards at the outer angle of the distal extremity, 

 the perforation being closed by the partially confluent epiphysis forming the articular surface 

 for the radius and ulna. 



944. The right radius and ulna of the same Trionyx. 



