204 ON THE DERMAL ARMOUR OF JACARE AND CAIMAN 
outwards, concave posteriorly, convex anteriorly ; they are flattened 
from side to side below, but they end above in subcylindrical styloid 
extremities. 
In the ninth vertebra the neurocentral suture passes just above 
the base of the parapophysis ; it traverses the parapophysis in the 
tenth and eleventh vertebrae, while in the twelfth the parapophysis 
suddenly rises to the root of the diapophysis, and the suture lies far 
below it. The centra of the dorsal vertebre, as far as the thirteenth 
inclusive, have hypapophyses. The diapophyses of the ninth ver- 
tebra pass almost horizontally outwards, but are a good deal inclined 
backwards. In the succeeding vertebree up to the fourteenth or 
fifteenth, the diapophyses are, in addition, inclined upwards, the 
upward inclination being most marked in the tenth, eleventh and 
twelfth vertebra. From the fifteenth vertebra onwards, the trans- 
verse processes pass almost directly outwards, without either upward 
or backward inclination. The span of the transverse processes is 
greatest in the eighteenth and nineteenth vertebre, in which the 
distance between the extremities of these processes is 7} inches, a 
length about equal to that of the longest vertebral rib. 
The rib of the ninth vertebra is terminated by a single long and 
slender semicartilaginous process which does not unite with the 
sternum. Each of the vertebral ribs from the tenth to the seven- 
teenth vertebra inclusively, on the other hand, is united with the 
sternum, or its continuation, by two such semicartilaginous costal 
elements, which may be respectively termed sternal and lateral. The 
sternal elements of the ribs of the tenth and eleventh vertebrz are 
united with the sternum proper ; those of the next five vertebre are 
connected with its median backward prolongation, while those of the 
seventeenth vertebra are attached to the processes into which this 
prolongation divides posteriorly. 
The sternal costal elements are very broad and flat, and though 
the lateral ones are less so, they are wide and expanded. The lateral 
costal pieces of the eleventh to the sixteenth vertebre inclusively, give 
attachment to very large and flat, triangular, processus unctvat?. Those 
of the twelfth are 3? inches long and 12 inch wide at their widest part. 
The transverse processes of the twentieth vertebra bear rudimentary 
ribs. The centrum of the thirteenth vertebra is 1% inch long, and 
the vertebra is 3} inches high from the lower edge of the centrum to. 
the summit of the neural spine. The centra of the vertebrz retain 
nearly the same length to the twentieth caudal; but behind this. 
vertebra they are shorter, as are the anterior dorsal vertebra. The 
first caudal vertebra is provided with two styliform bones, which. 
