14 
MAMMALIA. 
J. Leidy believes that the genera Megacerops, Brontotherium^ Sym~ 
borodon, and Miobasileus, will all prove identical with TitanotheHurrij and 
that the number of species will be much reduced. P. Ac. Philad. 1874, 
pp. 165 & 166. 
On the distinctions between Symborodon and Titanotherium ; E. D. 
Cope, tom. cit. p. 224. d On the characters of the former ; id. Rep, U. S. 
Geol. Surv. 1873, pp. 480-485, pis. ii.-viii. 
^ Brontotherium ingens^sp. n. (foss.), O. G. Marsh ; Miocene of Colorado. 
Am. J. Sc. (3) vii. p. 85, pis. i. & ii. 
Symborodon^ g. n. (foss.), E. D. Cope. Types, S. bucco and S. alteros- 
triSf spp. nn. ; Miocene of Colorado. Various species of Megaceratops, 
Brontotherium^ and Miobasileus, are also referred to this genus. Pal. 
Bull. No. 15 ; Syn. Vert. Color. ; Rep. U. S. Geol. Surv. 1873, 
pp. 480-493. 
Rhinoceros. On horns from Borneo, indicating the existence there of 
a species allied to R. sondaicus^ but smaller ; A. R. Wallace & A, Bartlett, 
P. Z. S. 1874, pp. 498 & 499 [c/. Zool. Rec. vi. p. 20]. 
^Rhinoceros sondaicus figured ; P. L. Sclater, tom. cit. pi. xxviii. 
Rhinoceros leptorhinus. On its skull, which appears to have had a 
complete nasal septum ; H. Woodward, Geol. Mag. (2) i. pp. 398-403, 
pi. XV. 
'^ceratherium guadriplicatum, from Miocene, and A. megalodus^ from 
Pliocene of Colorado, spp. nn. (foss.), E. D. Cope. Pal. Bull. Nos. 14 & 
15 ; Rep. U. S. Geol. Surv. 1873, pp. 495 & 520. 
Tapirus bairdi extends into South Mexico; P. L. Sclater, P. Z. S. 
1874, p. 89. 
Rhinochoerus sumatranus. On the colour of the young ; J. E. Gray, 
Ann. N. fi. (4) xiii. pp. 400 & 401. 
'^Hyrachyus is referred to this family, and the skeleton of H. eximius 
is described ; E. D. Cope, Rep. U. S. Geol. Surv. 1872, pp. 594-605. 
O. C. Marsh reviews the American fossil forms and their descent. 
New genera instituted are, Miohippus (p. 249), Miocene, with three digits, 
and no anteorbital fossa ; and Pliohippus (p. 252), Pliocene, with one 
digit and a large anteorbital fossa. The line of descent appears to be: — 
Eocene, Orohippus ; Miocene, Miohippus, Anchitherium ; Pliocene, An- 
chippus, Hipparion, Protohippus, Pleiohippus ; Quarternary and recent, 
Equus. New species described are — Orohippus major (p. 248) Wyoming 
and Utah ; Anchitherium anceps (p. 250), Oregon ; and A. celer (p. 251), 
Nebraska ; Pliohippus pernix (p. 252), and P. (p. 253), Nebraska ; 
Protohippus avus (p. 253), Oregon; and Anchippus brevidens (p. 234), 
Oregon. Am. J. Sc. (3) vii. pp. 247-258 \_cf. Ann. N. H. (4) xiii. p. 397, 
xiv. p. 167] ; Am. Nat. 1874, pp. 288-294. 
RniNOCEROTIDiE, 
Tapiridj]. 
Bquidao. 
