82 



NEW REPTILES AND STEGOCEPHALIANS FROM 



This structure of the posterior cervicals is very similar to the condition found in 

 Sellosaurus hermannianus Huene.^ 



The fifth of the series (first (?) dorsal) has the upper process on the side of the 

 neural arch; only its proximal portion is preserved, but it is apparent that it stood well 

 out from the side of the arch, forming a distinct transverse process. The lower process is 

 a triangular face on the lower edge of the anterior face of the centrum. In this vertebra 

 the zygapophyses and the neural spine have not been replaced. Due in part, but not 

 entirely, to compression, the centrum is notably shorter and heavier than the preceding 

 one and the posterior face of the centrum does not descend lower than the anterior. 

 The faces of the centrum are now vertical and larger than in the cervical series. Length 

 of the base of the centrum, 27 mm. 



The sixth of the series has a well-developed transverse process which stands out at 

 right angles from the high neural arch. This process is supported by two ridges running 

 from the upper edges of the anterior and posterior faces of the centrum to its base; 

 between these ridges and on either side of the base of the processes are deep pits. The 

 lower process is still visible as a small facet on the lower edge of the anterior face of the 

 centrum. The neural arch is high and the anterior and posterior zygapophyses rise at 

 a considerable angle instead of lying horizontal. Length of base of centrum, 27 mm. 



The seventh of the series has well-developed transverse processes; the extremities 

 are not replaced, but the base shows that they stood out at right angles to the neural 

 arch. The base is supported by four ridges running respectively from the anterior and 

 posterior zygapophyses and from the upper edges of the anterior and posterior faces 

 of the centrum. Between these ridges, on the anterior and posterior faces of the base 

 of the transverse process, there are deep pits. Upon this vertebra appears the last 

 trace of the lower process. The zygapophyses have not been replaced, but it is evident 

 that they rose at a decided angle from the neural arch. The lower edge of the centrum 

 is injured, but its length is approximately 32 mm. 



From this point in the series backward the vertebrae do not change radically. 

 The transverse processes increase shghtly in length and then decrease; the longest are 

 upon the tenth to the thirteenth. The zygapophyses are very steeply inclined upward 

 on the ninth and tenth and are less steeply inclined in the posterior vertebrae. The 

 centra become gradually heavier toward the posterior end of the series, and the bases of 

 the transverse processes are shorter anterio-posteriorly, due to the atrophy of the support- 

 ing ridges. In none of the vertebrae is there any sign of a median keel on the centra 

 or of any lateral ridges. The length of the base of the centrum of each is as follows: 



mm. 



13th 37 



14th (injured) 



15th 36 



16th 38 



These measurements are as accurate as possible, but are not quite as in nature 

 because of shght compression, breakage, etc., in the specimen. 



Fractures in the mid-line of several vertebrae show that the centrum was hollow, 

 but not so thin-walled as in Coelurus. The ribs are uniformly single-headed; one attached 

 to the fourteenth vertebra has a thin head 7 mm. wide; other rib-heads not located, but 

 apparently belonging to more anterior vertebrae, are nearly twice as broad.' The shaft 

 of the rib in certain parts of the series was T-shaped in section. The ribs are so badly 

 broken and the ends so injured by decay that only portions have as yet been reassembled. 



' Huene, F. v., Neues Jahrh. f. Gcol. Min. u. Pal. Jahrg., 1915, No. 1, Taf. 111. 



