HOLLAND AND PETERSON: OSTEOLOGY OF THE CHALICOTHEROIDEA. 207 
articulating with navicular only; Mt. III and IV of subequal length; fibula 
sometimes articulating with the os caleaneum; third trochanter of the femur 
strongly developed; fore and hind limbs more nearly of equal length than in 
Macrotherium. 
The foregoing generic characters are based upon the material representing 
Moropus elatus. It should not, however, be forgotten that Moropus distans from 
the John Day Beds of Oregon is the first species named by Marsh in his description 
of the genus, and is therefore the genotype. M. distans was a much smaller animal 
than M. elatus, even smaller than M. petersoni, and it may be that with the progress 
of discovery it will be found to be very different structurally from the animals 
represented in the Lower Miocene of Nebraska, so much so as to justify the generic 
separation of the latter. 
Genus NESTORITHERIUM® Kaup. 
Kaup, Beitrage, Heft IV, p. 3 (1859). (Type R. pachygnathus Wagner, partim = 
M. pentelicum Gaudry.) 
Synonym Ancylotherium Gaudry, Animaux fossiles et Géologie d’Attique, pp. 129- 
142 (1863). 
Type: Macrotherium pentelicum Gaudry et Lartet, Comptes Rendus de |’Acad. des 
Sciences, Vol. XLIII, p. 271 (1856) = Rhinoceros pachygnathus (Wagner) 
3 Wagner, in the Abhandlungen d. K. Bayer. Akademie d. Wissenschaften, II. K1., Vol. V, Abth. II, 
pp. 349 et seg. (1854), describes the remains of a rhinoceros, to which on Plate X (Tafel 2), Figs. 3, 4, and 5, 
and on Plate XI (Tafel 3) he applied the name of Rhinoceros pachygnathus. Subsequently, in 1857, in the same 
publication, Band VIII, Abth. I, p. 28 et seq., he describes a fragmentary skull, the left superior dentition of 
which he figures on Pl. VII, Fig. 15, to which he also applies the name of Rhinoceros pachygnathus (see our 
Fig. 3, which is drawn from a cast of the type). Later, in 1859, Kaup, recognizing that the dentition figured 
by Wagner (J. c.) did not pertain to a rhinoceros, but to a Chalicotheroid, erected the genus Nestoritheriwm for 
its reception. Falconer, writing from Munich, June 15, 1861 (see “Paleontological Memoirs and Notes of 
the late Hugh Falconer, A.M., M.D.,” etc., p. 223), says: “Most interesting of all the Pikermi collection are 
a set of specimens of a very large species of the same genus as our Sewalik Chalicotheriwm. This is the Nestori- 
therium Kaup (Beitrage, viertes Heft, 1859), which is figured and described under the name Rhinoceros pachy- 
gnathus by Wagner (1857). The principal specimen, Fig. 15, Plate VII, execrably drawn, consists of the greater 
part of a cranium,” etc. He then goes on to describe this specimen. It is thus clearly established that the 
Nestoritherium of Kaup was founded upon the Munich skull, which is undoubtedly referable to Ancylotheriwm 
pentelicum (Gaudry et Lartet), with which it has been identified by Zittel and others. The specimen is slightly 
smaller in size than the specimen in Paris, but, so far as comparison permits, identical. Bothcame from Pikermi. 
The genus Ancylotherium Gaudry was not proposed by the latter author until the year 1863 (cf. ‘ Animaux 
fossiles et Géologie d’Attique,” pp. 129 et seq.). From the foregoing it is seen that the generic name Nestori- 
therium has priority over Ancylothervwm, the type species being pachygnathum Wagner, a homonym, which 
must be dropped according to the laws of nomenclature, and replaced by pentelicum Gaudry et Lartet, which 
is identical, and also has priority. 
