416 INDEX GENERUM MAMMALIUM. 
Mesoreodon—Continued. 
Type: Mesoreodon chelonyx Scott, from the Miocene of Deep River Valley, north- 
west of White Sulphur Springs, Meagher County, Montana. 
Extinct. ‘‘Nearly all parts of the skeleton are known." 
Mesoreodon: uéGos, middle; + Oreodon. 
Mesorhinoceros (subg. of Rhinoceros) BRANDT, 1877. Ungulata, Rhinocerotide. 
Mém. Acad. Imp. Sci. St. Pétersbourg, 7* sér., XXIV, No. 4, pp. 120, 130, 1877; 
ibid, XXVI, No. 5, p. 58, 1878. 
Type: Rhinoceros leptorhinus Cuvier, from the Pleistocene of France. 
Extinct. 
Mesorhinoceros: uéGoc, middle; + Rhinoceros. 
Mesorhinus AMEGHINO, 1885. Ungulata, Litopterna, Macrauchenide. 
Bol. Acad. Nac. Cien. Cérdoba, VIII, entr. 1, pp. 94-97, 1885; Cont. Conocimiento 
Mamíf. Fósil. Repüb. Argentina, in Act. Acad. Nac. Cien., Córdoba, VI, 547- 
549, pl. xxii, figs. 11, 12, 1889. 
Type: Mesorhinus piramydatus [ pyramidatus] Ameghino, from the ‘ barrancas del 
Paraná, Argentina. 
Extinct. Based on the anterior portion of a cranium, including the intermax- 
illary and the anterior part of the maxillaries. 
Mesorhinus: uéGos, middle; pis, Ó1vóc, nose—in allusion to the intermediate 
position of the genus indicated by ‘‘la forma de la nariz, cuya apertura no está 
colocada tan hacia atrás como en Macrauchenia acercándose así mas á la forma 
comün en los perisodáctilos, y especialmente á la del caballo."  (l. c., 1885.) 
Mesotapirus Oszorn, 1889. Ungulata, Perissodactyla, Lophiodontide. 
Trans. Am. Philos. Soc., new ser., XVI, pt. 1, pp. 470, 524, Aug. 20, 1889. 
Type: Lophiodon occidentalis Leidy, from the White River beds of South Dakota. 
“The Miocene successor of /sectolophus is undoubtedly represented by the 
single three-lobed molar from the White River beds, which Dr. Leidy has 
referred to Lophiodon occidentalis. By analogy with the premolar evolution in 
all other perissodactyls we may anticipate that this tapir will be found to have 
three premolars like the molars ( Mesotapirus)." (OsBorn, 1. c. 524.) 
Extinct. 
Mesotapirus: é60s, middle; + Tapirus. 
Mesotaria Van BENEDEN, 1876. Fere, Pinnipedia, Phocidee. 
Bull. Acad. Roy. Sci. Belgique, 2° sér., XLI, 796-797, 1876. 
Type: Mesotaria ambigua Van Beneden, from the Antwerp basin, Belgium ( ‘‘dans 
la deuxiéme et la troisiéme section . . . ainsi qu'à Wommelghem, fort No. 2.’’) 
Extinct. ‘‘Représenté par la plupart des os du squelette, ainsi que par des dents 
et un os de pénis." 
Mesotaria: u£Goc, middle; +-Otaria. 
Mesoteras Corr, 1870. Cete, Baleenidee. 
Am. Naturalist, IV, 128, Apr., 1870; Proc. Am. Philos. Soc., XI, 286-291, 1870. 
Type: Mesoteras kerrianus Cope, from the bed of Miocene marl on Quanky Creek, 
Halifax County, North Carolina. 
Extinct. Based on ‘‘a large fragment of the cranium, including the greater part 
of the left maxillary and premaxillary bones, with a large part of the frontal. 
A large fragment of the right ramus of the mandible, an otic bulla, several 
lumbar and caudal vertebrze, with several broken ribs, were also obtained." 
Mesoteras: uéGoc, middle; rép«s, monster—probably in allusion to its size and 
occurrence in Miocene strata. 
Mesotherium Serres, 1857. Ungulata, Typotheria, Typotheriide. 
Comptes Rendus, Paris, XLIV, No. 19, pp. 961-962, Jan.-June, 1857; ibid, LXV, 
6, 140, 273. 429, 593, 740, 841, July-Dec., 1867; Gervais, Zool. et Paléont. Gén., 
I, 137, 1867 (species named). 
