244 



DINOSATJKIA. 



carina. Teeth (fig. 50) simpler than in Iguanodon, 

 with lozenge-shaped crowns, and the inferior 

 surface of the root of each tooth bearing a 

 groove for the reception of the summit of the 

 tooth below. 



Hadrosaurus is identified with Trachodon by 

 Leidy in the < Proc. Ac. Nat. Sci. Philad.' for 1868, 

 p. 199 ; the type tooth of the latter being figured 

 by him in the * Trans. Amer. Phil. Soc' vol. xi. 

 pt. 2, pi. x. figs. 1-6 (1859). 



Trachodon foulki, Leidy \ 



Syn. Hadrosaurus foulki, Leidy 2 . 



The distinction from T. mirabilis of the Judith- 

 River beds is not very apparent. Estimated 

 length 28 feet. 



Hah. North America. 



Fig. 50. 



Trachodon foulki. — 

 Tooth; from the 

 Upper Cretaceous 

 of New Jersey, 



R. 1007. Transverse section of a tooth; from the 



Upper Cretaceous of Huddersfield, New Jersey, U.S.A. 

 The dentition is figured by Leidy in his ( Cretaceous Eep- 

 tiliaof the United States' (Smiths. Contrib. Knowl. 1864), 

 pi. xiii., from which fig. 50 is copied. 



Presented by Sir B. Owen, K.C.B., 1884. 



Trachodon cantabrigiensis, Lydekker 3 . 



Nearly of the dimensions of T.foulJci, Fig. 51. 



but with the crowns of the teeth rela- 

 tively broader. 



Hab. Europe (England). 



R. 496. A tooth, wanting the base of 



(Fig.) the root; from the Cam- 

 bridge Greensand. The type 

 specimen (woodcut, fig. 51); 

 figured by Owen in his ' Cre- 

 taceous lleptilia' (Mon. Pal. 

 Soc), suppl. ii. pi. vii. figs. 

 16, 17, as Iguanodon man- 



Pbilad. for 1858, p. 218 (185' 



Irachodon cant 

 Lateral and profile views of 

 a tooth ; from the Cambridge 

 Greensand. \. 



1 Proc. Ac. Nat. Sci. 



2 Loc. cit. 



3 Quart. Journ. Gcol. Soc. vol. xliv. p. 47 (1888). 



-Hadrosaurus. 



