DISCOVEKY OF THE TITANOTHEEES AND ORIGINAL DESCRIPTIONS 



205 



Neotype (Osborn). — A carefully made model, based 

 on Leidy's figures and measurements of the lower jaw, 

 was compared with various specimens of Menodus 

 untn an upper dentition was found (in a skull, Am. 

 Mus. 505) which appears to fit very well the lower 

 teeth of the type. Hence the skull (Am. Mus. 505) 

 has been selected as a neotype of Menodus giganteus. 



Specific characters. — Not separated from the generic 

 characters in Pomel's description. (See p. 530.) 



Etymology. — giganteus, gigantic ; because larger than 

 the Palaeotherium magnum. 



Present determination. — Although Prout's original 

 specimen, the type of Menodus giganteus Pomel, has 

 been lost, Leidy's carefully executed figure of this 

 specimen, together with his measurements and descrip- 

 tions, reveals generic and specific identity with the 

 dolichocephalic titanothere which Osborn in 1902 

 designated (1902.208, p. 96) Titanotherium ingens 

 Marsh. Titanotherium ingens is therefore to be 

 regarded as a synonym of Menodus giganteus Pomel. 



Type. — From a study of the foregoing references it 

 is evident that Owen, Norwood, and Evans intended 

 the name Palaeotherium? proutii to cover both Prout's 

 original specimen and "Owen's specimen," discovered 

 by Evans, the lower jaw which was figured by Leidy 

 in 1852 (1852.1, pi. 9, figs. 3, 3a) and is still preserved 

 in the United States National Museum (No. 113; 

 our fig. 160). Prout's specimen is the type of Meno- 

 dus giganteus Pomel; hence, by the method of elimina- 

 tion, Owen's specimen becomes the type of Palaeothe- 

 rium? proutii Owen, Norwood, and Evans. 



Etymology. — Named in honor of Dr. Hiram Prout. 



Present determination. — "Owen's specimen" (Nat. 

 Mus. 113) appears to represent a Menodus, of a stage 

 slightly smaller than M. trigonoceras. (See p. 528.) 



Titanotherium Leidy, 1852 

 Cf. Menodus, this monograph, page 522 



Original reference. — "Palaeotherium? proutii Owen, 

 Norwood, and Evans," Owen, Eeport of a geological 



Y 



'<j. 



\y\ 



Figure 160. — Owen's specimens of Palaeotherium? -proutii 



After Leidy, 1862. A, Type of Palaeolheriumf proutii (Owen's specimen), Nat. Mus. 113. One-third natural size. Ttiis was the 

 principal specimen referred to by Leidy in proposing the name Titanotherium (1852.1). B, Third left lower molar, another of 

 Owen's specimens used by Leidy in describing Titanotherium. Two-thirds natural size. 



EARLY NOTICES BY lEIDY AND OTHERS, 1850-1870 

 Palaeotherium? proutii Owen, Norwood, and Evans, 1850 



Cf. Titanotherium proutii Leidy 



Original reference. — Acad. Nat. Sci. Philadelphia 

 Proc, vol. 5, p. 66, August, 1850 (Owen, Norwood, 

 and Evans, 1850.1). 



Subsequent reference . — " Palaeotherium? proutii Owen, 

 Norwood, and Evans," Leidy, Description of the 

 remains of extinct Mammalia and Chelonia from 

 Nebraska Territory, in Owen, Report of a geological 

 survey of Wisconsin, Iowa, and Minnesota, pp. 551- 

 552, tab. 9, figs. 3a, 3, 1852 [Owen's specimens, not 

 Prout's] (Leidy, 1852.1); "Titanotherium proutii 

 Leidy," The ancient fauna of Nebraska, pp. 72-73, 

 pi. 16, figs. 1-3, 1853 (Leidy, 1854.1). 



Original description. — Owen, Norwood, and Evans 

 state that 



These remarkable remains are thus named in compliment to 

 Dr. Prout of St. Louis who first noticed them in the American 

 Journal of Science and Arts. The generic characters, however, 

 are not yet satisfactorily decided. 



survey of Wisconsin, Iowa, and Minnesota, p. 552 

 1852 (Titanotherium) (Leidy, 1852.1V 



Subsequent reference. — " Titanotherium proutii 

 Leidy," Leidy, The ancient fauna of Nebraska, pp. 

 72, 114, 1853 (Leidy, 1854.1). 



Type species. — Palaeotherium? proutii Owen, Nor- 

 wood, and Evans."* (See p. 526.) 



Generic characters. — Not separated by Leidy from 

 specific characters. 



Etymology. — 'Yirkv, a Titan; driplov, beast. 



Present determination. — Leidy based the genus Ti- 

 tanotherium collectively upon a number of specimens, 

 including, first, Prout's original specimen; second, 

 "Owen's specimen" (Nat. Mus. 113); and third, cer- 

 tain other fragmentary specimens. Prout's specimen 

 was already the type of Menodus giganteus Pomel, 

 hence by elimination the genus Titanotherium rests 

 upon the species Palaeotherium? proutii Owen, Nor- 



i« In his work of 1853 Leidy placed his own name after the speoihc name proutii, 

 evidently following the practice of those who placed the name of the author of the 

 genus after the specific name. 



