28 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 16, 
Part IV.—Description of a portion of the Skull and Upper Teeth 
of the same species of Paloplotherium (P. annectens). 
(Pl. IIT. figs. 1 & 2.) 
THe Paleotherium which Cuvier found to deviate most from the 
generic characters of those of Montmartre (Pal. magnum, P. crassum, 
P. medium, P. curtum), which may be viewed as the types of the 
genus, is the species from Orleans already referred to (’ espéce d Or- 
léans of the ‘Ossemens Fossiles,’ 11. p. 254; Paleotherium Aure- 
lianense, Auct. De Bl. Ostéog. fase. xxi. (1847) p. 43). 
The differences specified by Cuvier are those presented by the 
molar teeth. In the upper (true) molars ‘ the distinctive character’ 
of the ‘ Pal. d’Orléans’ consists in this, that the lobes or ridges (PI. III. 
fig. 6 , 2) (collines) which extend from the external border, at their 
arrival at the mternal border do not come back; and in this, that 
there is at the posterior border a little insulated ‘colline’ in the form 
of a chevron*. 
It is assumed in the ‘Ossemens Fossiles’ that the number of the 
permanent molars m the Pal. Aurelianense is the same as in the 
other species ; in short, that it presents the numerical formula of the 
genus Paleotherium: and Cuvier, therefore, interprets the modifi- 
cations of the grinding surface of the upper molar as a specific dif- 
ference. ; 
M. Hermann V. Meyer, on the other hand, has founded a genus} 
on a few fossil teeth, from the tertiary deposits near Madrid, which 
present the same modifications of the grinding surface, and belong 
apparently to the same species as the Paleotherium Aurelianense. 
Not any of the fossils, however, described and figured by Cuvier, 
Guettard, or M. V. Meyer, and which are referred in the systematic 
Paleontological Treatisest to the Paleotherium Aurelianense, exhibit 
the whole series of molars in either upper or lower jaw. The question 
of the generic distinction of this Paleeotherioid must therefore remain 
in abeyance until further evidence, and especially the important cha- 
racter of the dental formula is determined ; for few anatomists or 
naturalists, I apprehend, will be found to regard as generic the di- 
stinctive characters of the Orleans Palzeothere, specified by Cuvier. 
Ample grounds, however, for so interpreting the fossil cranium 
under consideration (Pl. III. figs. 1 & 2) are furnished by the entire 
series of molar teeth in the upper jaw, which consist on each side of 
three molars (M 1, 2 & 3) and of but three premolars (P 2, 3 & 4), 
instead of four premolars as in the typical Palgotheria: the sockets 
* Tom. cit. p. 255, pl. 67. figs. 11 and 12. Cuvier also cites a figure by 
Guettard of one of these molars, in the ‘ Mémoires sur les Arts et les Sciences,’ 
tom. v. pl. 7. fig. 1;—a work which I have not had the opportunity of con- 
sulting. 
T Haphitheriun Equerre ; Jahrbuch fiir Mineralogie, 1844, p. 298. 
{ Picrer, ‘ Traité Elémentaire de Paléontologie,’ t. i. (1844) p. 274. GrEBEL, 
‘Die Saugethiere der Vorwelt,’ 8vo. (1847) p. 189. 
