26 KANSAS UNIVElvSITY QUARTERLY. 



The relative proportions of the different regions in the two genera, 

 as shown by the two specimens of Clidastcs and Liodou, may be repre- 

 sented as follows. The first column is for Clidaitcs. 



Skull 12. 1 II. I 



Neck 6.5 6.8 



Trunk 39. 2 28.0 



Tail 42.3 54. 1 



Limbs. 



The figures in plates II and III will give a sufficiently good idea of 

 the limbs in this specimen. They are figured as they were lying, show- 

 ing the outer sides of the coracoid, scapula and pelvic bones, and 

 the palmar or plantar surface of the remaining bones. 

 Coracoid. 



It will be observed in plates II and IV that there are two very 

 different types of coracoid, one with a deep emargination, the other 

 without the slightest indication of such. The same non-emarginate 

 form occurs in C. tortor, as specimens in our Museum show, in C. 

 propython Cope (Ext. Batr. etc. pi. xii, f. 16,) and in C. dispar, as 

 figured by Marsh*, and as stated by him in the same paper ("There 

 is certainly no emargination in the coracoid of Clidastes, Edestosaurus 

 and Baptosaurus, as specimens in the Yale Museum conclusively 

 prove.") It is true that Marsh in a later paper f figured a specimen 

 with emarginate coracoi_,d under the name of Edestosaurus dispar, but 

 it is certain that his identification of his own species was wrong, as 

 will be seen by comparing his figures. From the senior author's 

 memory of the specimen with the emarginate coracoid figured, and 

 from the figure itself he feels confident that the second specimen is C. 

 velox. 



That the emargination was overlooked by the author seems strange, 

 as in the same paper in which this figure is given occurs the descrip- 

 tion oi Holosaurus, founded upon that very eharaeter. If the emargi- 

 nation is sufficiently important to base a genus in the one case, then 

 it should be in the other, and the character could not be applied to 

 Edestosaurus, based upon characters which it hardly seems possible 

 that the author himself could seriously consider, for E. dispar was the 

 type of Edestosaurus. 



It will be observed, further, that the figured coracoids differ very 

 materially in size, those with the emargination pertaining to a small 

 species, while C. dispar is one of the largest. In our Museum there 

 are three specimens with the emarginate coracoid, all of them small or 

 very small, the described specimen of C. velox being the largest. 



*Amer. Journ. t^ci. iii, pi. xi, f. 1, June, 1872. 

 f Amer. Journ. Sci. xix, pi. i, fig, 1, Jan., 1880. 



