294 



PROCEtlDtNGS OF THE I^ATIONAL MtJSEVM. vol. xxxvi. 



preacetabular process is terminated by a somewhat more angularly 

 pobited end than the rounded, more spatulate type found in C. 

 dispar (see fig. 29). AVith the exception that the ischiac process 

 is not so robust, in nearly all other respects the ilia appear very 

 similar to those of the better known species. The contour of the 



posterior end, due to the 

 '; damaged condition of both 

 ™ elements, can not be de- 

 j termined at this time. 

 2 Turning now to the sa- 



5 oral and caudal vertebrae 

 E^ associated with the ilia, it 

 = may be observed that the 

 H sacrals are characterized by 

 '' the ankylosis of all their 

 ^ centra and their quite 

 I evenly rounded haemal sur- 



1 K faces, there being just the 

 5 M faintest indication of the 

 i g presence of a median keel 



2 S upon Sacrals I, 11, and 

 ^ 2 III. None shows the flat- 

 :" 2 tened ventral surfaces ob- 

 ^ served in the paratype of 

 ^ i C. dispar, No. 1877a, Yale 

 ^ " Museum. In this respect, 

 ■2 except in size, they more 

 ^ nearly resemble the sacrals 

 ^ of C. nanus. 

 i From the fragmentary 

 ^ evidence, it appears there 



1 were at least seven verte- 

 ^ brae ankylosed by their 

 f centra in this region, the 

 J most anterior of which is 



2 a sacro-dorsal, the poste- 

 rior one likely representing 



a sacro-caudal, as in C. hrowni. Attached to the rock, which also 

 holds the left ilium, are a number of spinous processes, which, if 

 they pertain to the sacrum, show the spines as being much narrower 

 antero-posteriorly, and without the heavy expanded tops of C. dispar. 

 The caudal centra show no distinctive characters, but, as in the 

 other species, the anterior caudals show the same obliquity of the 

 centrum, the small neural canal, the wide transverse processes, and 

 the slightly biconcave cupping of the articular ends, The diameter 



