HY ANODONTID&. Dit. 
Genus HY ZENODON, Laizer and Parieu’. 
Syn. Taxotherium, Blainville? (teste P. Gervais). 
Eutemnodus, Bravard, MS. 
Dentition :—I. 5, C. > Pn. a M. 2 Cope® gives the number of 
cheek-teeth as Pm. x M. , reckoning the fourth upper tooth as a 
‘molar instead ofa premolar. If, however, the crania of Hycenodon and 
Pierodon, figured by Filhol in the Ann. Soe. Sci. Phys. Nat. Toulouse, 
1882, pls. i. & 11., be compared together, it will be pretty evident 
that the fourth cheek-tooth in the two specimens is homologous ; 
and it is quite clear that this tooth is a premolar in Pterodon. 
Filhol, in the Ann. Sci. Géol. vol. vii. art. 7, p. 211, remarks that 
Hycnodon vulpinus differs from all the other species by the presence 
of six in place of seven upper cheek-teeth ; but the present writer 
has never seen any instance of the presence of m.3 in any species, 
and it is certainly wanting in all the specimens figured by Filhol. 
The genus is abundantly distributed in the Lower Tertiaries of 
Europe and North America, and one species (or a closely allied 
form) has been described from the Siwaliks of India (vide infra). 
Hyzenodon heberti, Filhol’. 
This is the largest European species of the genus. It has not 
hitherto been recorded from Vaucluse. 
Hab. France. 
26749. The greater part of the right ramus of the mandible’, con- 
taining the whole of the cheek-dentition and the canine ; 
from the Upper Eocene of Débruge, near Apt (Vaucluse), 
1 Comptes Rendus, vol. vii. p. 442 (1838). 
2 ‘Ostéographie, Genus Subursus, p. 55 (1841). Taxotherium is identified 
with Hyenodon on the authority of P. Gervais (Zool. et Pal. Frang. 2nd edit. 
pp. 282-235) ; but it is very doubtful what Zaxotherium (Hyenodon) parisiense 
really is. Gervais refers Pomel’s Pzerodon cuviert to it ; but that species seems 
to be the same as Pterodon dasyuroides. 
3 Amer, Nat. 1884, p. 345. 
4 Bull. Soc. Philom. Paris, ser. 6, vol. xi. pp. 16-21 (1874). 
5 This and other specimens from Vaucluse have been hitherto labelled 
H. requieni; but they are of much larger size, as will be shown below. Some 
(e. g. No. 28203) are entered in Bravard’s MS. Catalogue as Hutemnodus eury- 
rhynchus, Bravard. The same generic term has been employed by Bravard 
(vide H. Gervais and Ameghino, ‘Les Mammiféres fossiles de l Amérique du 
Sud,’ p. 21 [1880]) for a fossil Carnivore from the Pleistocene of 8. America, 
which cannot now be identified. It would be very remarkable if Hyenodon 
were found in those deposits. 
