Cope.] 



110 



[Feb. 2, 



Posterior part of right side of skull of Cmoliasaurus snovii Willist. 

 Modified after Willistou. 



I embrace the present opportunity to correct an error into -wliich I inad- 

 vertently fell when naming the elements of the cranium in tlie Coty- 

 losauria, in the essay above quoted. That segment which forms the 

 lateral angle of the superior table of the skull in the Cotylosaurian rep- 

 tiles, the Stegocephalous batrachians, and many fishes, is there termed the 

 OS intercalare, after Cuvier. It is, however, not his intercalare, but his 

 external occipital. This is the epioiic of Huxley, but as it is not homo- 

 logous with that element in the Reptilia, it requires another name. I 

 propose that it be called the os tahulare, or the tabular bone. I do not 

 know of any reptiles otlier than the Cotylosauria in which it is present ; 

 (see PI. X, Tab.). 



I refer in this connection to a taxonomic question wliich depends on a 

 correct knowledge of the posterior part of tlie Reptilian skull. Huxley* 

 referred the Triassic genus Telerpetou to the Lacertilia, and I afterwards f 

 endeavored to show that this genus, together with Rhynchosaurue, 

 Hyperodapedon and Saurosternum belong to the Rhynchocephalia. In 

 this I have been followed by most authors who have since treated of the 

 subject. After a study of the cranial arches, I became convinced that 

 these genera could not be Rhynchocephalia, J since they possess but one 

 postorbital bar, while the Rhynchocephalia possess two. In the papers 

 cited below I placed them in the Theromora in the subdivision Progano- 

 sauria, and associated with them the Proterosauriidaj. It has become evi- 

 dent that this is their true position, and that they are not far removed 

 from the Anomodontia, with which they were nearly contemporary in 



* Quarterly Joum.. Geolog. Society, London, 18C9, p. 49. 

 ^ Proceeds. Amer. Assoc. Adv. Hci., 1870, Vol. xix, p. 241. 

 t "Synopsis of the Families of Vertebrata," American Naturalist, Oct., 1889. 

 of Lectures on Vertebrata Univ. of Pennsylvania, July, 1891, p. 33. 



Syllabus 



