182 UNeULATA. 



Genus DINOCERAS, Marsh \ 



Including Octotomus, Cope 2 . 



Dentition :— (usually) I. g, C. \, Pm. |, M. |. 



The base of the upper canine is nearly vertical, the cervical 

 vertebrae are longer than in Tinoceras> and the lunar articulates, 

 with the trapezoid. 



Dinoceras laticeps, Marsh*. 



Syn. Octotomus latieeps, Cope 4 . 

 Hab. North America. 



M. 2060. Cast of the mandible. The original! is from the Bridger 

 Eocene of Wyoming ; and is figured by Marsh in the 

 * Monograph of the Dinocerata,' pi. xiii. 



Presented by Professor 0. C. Marsh, 1885-. 



Dinoceras mirabile, Marsh 5 . 



Syn. UintatTierium mirabile, Cope 6 . 



The mandible is unknown. 



Hah. North America. The originals of all the following speci- 

 mens were obtained from the Bridger Eocene of Wyoming, and 

 are figured in Marsh's ' Monograph of the Dinocerata/ All the- 

 casts were presented by Professor 0. C. Marsh, 1885. 



M. 2058. Cast of the cranium. 



M. 2059. Cast of the brain- cavity. 



M. 2072-76. Casts of the bones of the fore limb. 



M. 2081-83-89. Casts of the bones of the hind limb. 



M. 2087-88. Cast of the left astragalus and calcaneum. 



M. 2062-71. Casts of the anterior vertebrae. 



M. 2082. Cast of the sacrum. 



M. 2090-91. Casts of two caudal vertebrae. 



It. 2077-81. Casts of four ribs. 



1 Amer. Journ. ser. 3, vol. iv. p. 344 (for Oct., published in advance Sept 

 27, 1872). 



2 Amer. Nat. vol. xix. p. 44 (1885). 



3 Amer. Journ. ser. 3, vol. vi. p 301 (Oct. 1873). 



4 Amer. Nat. vol. xix. p. 52 (1885). 



5 Amer. Journ. ser. 3, vol. iv. p. 344 (Oct. 1872). 



6 Eep. U. S. Geol. Surv. Terr, for 1872, p. 581 (1873), 



