Species o/'Saurocephalus. 481 



nature of the remains * (although he confounded them with, 

 an entirely distinct species) ; and his conclusions were con- 

 firmed by Kichard Owen f. Dr. Leidy J corrected Agassiz's 

 errors, and gave more accurate descriptions and figures of 

 the maxillary than had been furnished by Harlan. 



No remains of Harlan's species, other than the maxillary 

 referred to, have hitherto been described. Dr. E. W. Hil- 

 gard § has reported the species as occurring in the Vicksburg 

 group of the Eocene, but the identification was undoubtedly 

 erroneous. Dr. William Spillman || has also included this 

 species in his list of fossils belonging to the Tombigbee 

 greensand of the Cretaceous at Columbus, Miss. Although 

 this identification is less improbable than the former, we have 

 nothing to confirm its correctness. 



Notwithstanding the scantiness of the material belonging 

 to the type species, our knowledge of the genus Sauro- 

 cephalus has been greatly increased through the descriptions 

 of closely related and more perfectly preserved species. For 

 this additional knowledge we are indebted to Cope and 

 Newton, and more recently to Alban Stewart, of the Uni- 

 versity of Kansas. 



For some time I have had in my possession some remains 

 which on examination prove, in my judgment, to belong 

 to Harlan's species. This material was collected for me in 

 the region of Butte Creek canon, south of Wallace, Kan. ; 

 and the horizon is undoubtedly that of the Niobrara Creta- 

 ceous. My material consists of both the mandibles, the right 

 maxilla, the pterygo-palatine arch, and a few other bones. 



The maxillary (fig. 1) is rather short and deep. The 



Fio- 1. 



portion belonging in front of the palatine condyle is missing; 

 but the condyle itself is present. The alveolar border is 



* Poiss. Foss. v. p. 102. t Odontography, p. 130, pi. 55. 



\ Trans. Amer. Philos. Soc. 1857, xi. pp. 91-95, pi. vi. tigs. 8-11. 

 § Report Geol. & Agric. Mississippi, I860, p. 112. 

 || Op. cit. p. 389. 



