1847.] OWEN ON EXTINCT ANTHRACOTHERIOID QUADRUPEDS. 111 
mens Fossiles’ (1824), by the subsequent acquisition of the almost 
entire upper jaw discovered by M. Bertrand de Doué in the ‘ Bassin 
du Puy’; and by a crushed cranium with the dental system tolerably 
complete, and portions of the lower jaw, discovered in the same loca- 
lity by M. Bravard. With regard to the upper true molars in these 
specimens, M. de Blainville says that in proportion to those of the 
other Anthracotheria, they are “plus large que longues,” “et que 
les collines transversales de la couronne sont bien plus prononcées par 
la profondeur de la gouttiére qui les sépare, et parceque les deux points 
de chacune sont plus détachées et plus aigués, avec le bord externe 
bien plus versant en dedans et plus anguleusement sinueux.”’ All 
the teeth, M. de Blainville adds, “‘offrent en outre une particularité 
différentielle remarquable, en ce qu’elles sont constamment comme 
stri¢es ou plissées verticalement, surtout vers le collet.” 
After his comparison of the rich materials at present accumulated 
in the Parisian museums of Paleeontology, M. de Blainville sums up 
the dental characters of the genus Anthracotherium as follows :— 
is capiaama Meggan ae erin 
Formula git i + Z dont 3 + i + 3? 
which signifies that there are 3 incisors, 1 canine and 7 molars on 
each side of both upper and lower jaws; and that of the 7 molars 3 
are ‘avant-molaires,’ ] ‘la principale,’ and 3 are ‘vraies molaires.’ 
The tooth here called ‘principale’ being the last, or fourth pre- 
molar. ; 
“<The incisors are sublateral above, terminal and procumbent be- 
low. The canines of moderate size and pretty much curved (‘mé- 
diocres, assez arquées’). The three anterior premolars with conical, 
more or less compressed crowns, with two roots above as well as be- 
low: the first equidistant ; the fourth (‘principale’) below appearing 
like a moiety of the true molars. The upper true molars formed of 
two transverse ridges, each divided into two points, the outer one 
foliaceous, the imner one conical. The lower true molars with the 
transverse ridges elevated into a point at their extremities; the last 
molar provided with a pretty strong third ridge *.” 
To the genus Anthracotherium, as defined by such characters, it 
would be easy to refer the fossils from the Isle of Wight now under 
review ; but it becomes necessary to consider the value of the differ- 
ences observable in these fossils, as compared with the first-defined 
Anthracotheria, and by aiming at a true interpretation of those dif- 
ferences, to endeavour to give more precision to the definition of the 
true genus Anthracotherium. 
The differences presented by the upper molar (Pl. VII. figs. 1-5) 
of the Anthracotherioid from the Isle of Wight from that of the true 
Anthracotherium (ibid. fig. 9, m 3) have already been pointed out ; 
and with regard to the value of these differences it may be remarked, 
that the ultimate molars of Camelus, Camelopardalis, Alces and Bos 
show a less amount of difference of structure from one another than 
exists between the molar of the Hyopotamus bovinus and that of 
* Eves pide 
