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jaw. The ordinal characters are further manifested in the vertebral column of the trunk. 

 Pleurapophyses commence at the atlas, and in the succeeding vertebrae are articulated to two 

 points of their respective vertebrae, viz. by a head and tubercle to a dia- and par-apophysis. 

 From the third to the seventh cervical the pleurapophyses are short and peculiarly developed 

 in the direction of the axis of the trunk both forwards and backwards, overlapping each other ; 

 the pleurapophyses of the eighth vertebra are long and slender, extend outwards, and termi- 

 nate in a point ; those of the ninth vertebra join the sternum by partially ossified hsemapo- 

 physes : the same structure is presented by the six following ribs : in the next four vertebrae 

 the cartilages join each other, and are united to the sternum through the medium of the car- 

 tilage of the fifteenth pleurapophysis ; in the twenty-first vertebra the pleurapophyses are re- 

 duced to small styliform rudiments appended to the extremity of the diapophysis. 



From the third to the ninth vertebra inclusive the head of the rib articulates to the lower 

 transverse process or parapophysis, and the tubercle to the upper transverse process or dia- 

 pophysis : in the thirteenth vertebra the head of the rib ascends and articulates to the base of 

 the diapophysis, the tubercle still adhering to the apex : in the fourteenth vertebra the head 

 of the pleurapophysis applies itself to a notch in the fore-part of the diapophysis, and in the 

 twentieth vertebra the head finally disappears. The twenty-first to the twenty-fourth verte- 

 brae inclusive show no rudiments of ossified pleurapophyses, but the haemapophysial parts of 

 the ribs are present as long and slender cartilages in the abdominal parietes. If we begin to 

 count the dorsal series of vertebrae from that in which the rib is complete, or consists of both 

 pleurapophysis and haemapophysis joining the sternum, and include in the dorsal series the 

 succeeding vertebrae which have freely articulating pleurapophyses, there are then twelve 

 ' dorsal ' vertebrae. The eight vertebrae anterior to these may be called ' cervical,' and the four 

 posterior to them ' lumbar.' The sacral vertebrae are two in number, and characterized, as 

 in the Lizards, by their short and thick pleurapophyses ; the sutures uniting which to the 

 diapophyses are still obvious in this skeleton : the second sacral vertebra differs in the Croco- 

 dilia from that in the Lacertilia by presenting a concavity or cup to the first caudal instead 

 of a ball ; the second caudal vertebra recovering the ordinary position of the cup and ball. 

 The haemapophyses are articulated to interspaces of the caudal vertebrae, but chiefly to 

 the centrum of that to which they properly belong, viz. the anterior one : they are confluent 

 at their lower extremities, which are produced into a haemal spine. The transverse pro- 

 cesses, formed by the anchylosed depressed pleurapophyses, are developed from the fourteen 

 anterior caudal vertebrae. The remainder of this series bear compressed, high, slender neural 

 spines, which progressively decrease in length to the end of the tail. 



The hyoid arch consists of a broad cartilaginous and partially ossified basihyal, and two 

 simple, slender, bent, bony ceratohyals. 



The scapular arch consists of a simple scapula and coracoid, both formed by compressed, 

 narrow, moderately long plates of bone, thickest where they are united together to form the 

 glenoid cavity for the humerus. The ilium is a very short but thick bone : the inverted arch 

 formed by the pubes is quite distinct from that formed by the ischia : all the three bones 

 combine as usual to form an articular cavity for the femur. 



The character of the genus Crocodilug is manifested in this specimen by the reception of 

 the fourth tooth, or canine, of the lower jaw in a notch of the lateral margin of the upper 



