44G THE WASATCH FAUXA. 



pophv.sial plate is most contracted at the junction of the second and third 

 centra. Beyond this point the edge narrows, becomes more prominent later- 

 ally, becomes thin-edged, and then narrowly truncate again. The neural 

 spines are compressed, and are well developed on all the centra, that of the 

 •second having the largest anteroposterior diameter. The articular face of 

 the last centrum is a deep transverse oval. 



The caudal vertebrae are represented by eleven centra and paiis of cen- 

 tra. They indicate a long robust tail ; probably rather more robust than 

 that of the lion, but not so prolonged. As in most Mammalia with long tail, 

 the proximal centra are short and r ibust, and they successively increase in 

 length to past the middle of the series. The distal centra are rather smaller 

 than those of the lion or hunting leopard. On the anterior centra the dia- 

 pophyses are robust and elongate, and are directed posteriorly. Their pos- 

 terior base is at the posterior articular face. They are triangular in sec- 

 tion, owing to the presence of a ridge which, on the superior aspect, extends 

 diagonally backwards. As the diapophysis becomes reduced to a hook on 

 the posterior extremity of the centrum, a prominence arises in the same 

 line at a point marking the anterior third of the length. As the dia- 

 pophysis diminishes, this process increases in length, but both processes are 

 tinall}- reduced to mere tubercles. The articular faces are slightly opistho- 

 coelous They are round in the anterior part of the series, and become 

 more depressed posteriorly. This is chiefl}- due to a flattening of the infe- 

 rior side. When the neurapophyses fail to meet above, they remain as 

 crests and thin ridges, on the posterior extremity only of the centrum, 

 while the prezygapophyses remain as prominent widely separated processes 

 at the anterior extremity of the centrum. The inferior face of the anterior 

 centra is ribbed below ; the rib widens at the extremities, its angles at the 

 posterior edge probably giving attachment to the chevron bones. This 

 flattened rib is finally represented at the extremities of the centrum only, 

 and disappears first at the ])osterior extremity. 



Measurements of vertebral column. 



it. 



Li'UKth nf cerviciil series 180 



Lciigtb of dorsal »eries 6t*t 



Length of siicrul series 140 



