1G2 



supposed that sixty caudal vertebrae is below rather than above the true 

 number. 



The cervical and dorsal vertebrae have been slightly crushed, as they laid 

 on the side, and present a narrower diameter than is normal ; the cup of 

 the cervical has not been distorted, and is deeper than wide, presenting the 

 character of Macrosaunis. The rudimental zygosphen consists of a continu- 

 ation of the roof of the neural canal in front, to adapt itself to the inner face 

 of the down-looking zygapophysis of the preceding vertebra. The latter is 

 thus received into a groove on the inner side of the up-looking posterior zyga- 

 pophysis. The dorsals and candals exhibit, with the cervicals, that minute, 

 sharply-defined rugosity which characterizes all the projecting margins, 

 especially those of the hypapophyses and diapophyses, in this genus and 

 Clidastes. The whole surface of the cervical is marked with either inoscu- 

 lating striae or impressed punctse. The same character marks the cranial 

 bones, though they do not present such rugosity as the vertebrae. 



The proximal caudal presents a subhexagonal section, of which the infe- 

 rior and supero-lateral sides are longest; articular faces about as broad as 

 high. A broad, smooth space between the chevron-bones. Diapophyses with 

 broad, ovate transverse section. 



A caudal without diapophyses, anterior to the middle of the series, esti- 

 mated by the size, is but slightly deeper than long, and with parallel lateral 

 outlines of the articular faces. The neural arch is very much narrowed antero- 

 posteriorly, but has a greater transverse extent at its lowest part ; above, the 

 spine is much compressed, but not widened. The zygapophyses remain as 

 rudiments just above the small neural canal, but do not probably touch each 

 other. There are two anterior and two posterior narrow ribs on the upper 

 portion of the neural spine. The more distal caudals have wider neural 

 spines, and the arch has also a greater antero-posterior extent. The zyga- 

 pophyses are scarcely traceable, and the neural spine is strongly striate. The 

 reverse arrangement is observed in Clidastes propytlion, where the neural 

 spine of the proximal caudal has considerable extent, while those of the pos- 

 terior and distal vertebras are almost cyliudric, especially the neurapophyses. 



Dimensions. 



Inches. 



Dorsal, length 3.25 



Dorsal, width of the cup 2.50 



Dorsal, depth of the tup 2.77 



Proximal caudal, leugth 2. 14 



