178 
TERTIAEY VERTEBRATA OF THE FAY&M. 
Suborder ART 10 DACTYL A. 
Family ANTI I UACOTIIEIIIID.F:. 
Genus ANCODON, Pomel. 
[Arcliiv. Soi. Phys. et Nat., Geneve, [4] vol. v. p. 207 (June 1847) (as a subgenus 
of Palaotlierium.A 
1818*'. Bothriodon., Aymanl, Ann. Soc. Agric. Sci., Arts, et Coinni. du Pny, vol. xii. pp. 239, 
24()-247, foohiote (as a sul)genus ot' AnllLracotheriuin'). 
1848. 7A/opot(Z»n/5 1, Owen, Quart. Journ. Geol. Soc. vol. iv. p. 103. 
1848. Ancodutf, l^oniel, op. cit. xupva, [4] vol. viii. pp. 324-.') (raised to generic rank, and 
unnecessarily emended from Ancodon). 
At least two species referable to this genus occur in the Upper Eocene beds of the 
Eayiim, and from the comparative abundance of their remains these animals seem to 
liave been very common in the later Eocene period. As might be expected from their 
somewhat earlier date, the species here desciibed are rather more primitive in their 
tooth-structure than are the forms from the Oligocene of Europe and America. This 
is especially noticeable in the more brachyodont and less selenodont character of the 
molars, which resemble to some extent those of Anthracotherium, but are still more 
like those of the much later (L. Miocene) genus Brachyodus, remains of which, it 
is interesting to note, have been found at Moghara, to the north-west of the Fayum. 
It may eventually be necessary to separate the present species from Ancodon, but on 
account of the great general resemblance of the lower jaw of yl. to that ot‘ 
some of the European forms such as A. velannus, it seems desirable, until a more 
distinctive character than the slight ditl'ereuces in the teeth above referred to has 
been found, to retain the same generic name for both. 
The skeleton in this genus has been described in detail by KowalevskyJ, Filhol §, 
Scott II , and others, so that here it will only be necessary to give a short account of 
the various specimens in the collection under their several numbers in the list below. 
* There i.s some doubt about tins date, since while tlie tillepage of the volume is dated 1843, the cover 
has 1848. In s[)ite of the fact that it has been authoritatively stated (see Bush, Aiiiei'. Journ. 8ci. [4J 
vol. xvi. (1903) pp. 97-98) that this volume was printed in 1847, it seems probable that the date on the 
(;over represents the date of issue (i. e. of publication), particularly as the autbor’.s se])arate co[)ies are 
known to have been dated 1848 also. This being the case, it seems desirable to adopt I’omel’s name Ancydon 
of 1847 for Hie genus. 
t Preoccupied in 1814 by Kaup for a genus of 41 ijiiiopotamidac. 
X “()n the Cl.steology of the llyojiotamidai,” Phil. 'I'l'ans. 1873, j). lit. 
^ Ptudes des Mammiferes fo.ssiles de Ronzon,” Annalo.s des Sciences (Icologicpies, vol. xii. (1882). 
II “Structure and RelaHon.shiiis of Ancodus,'’ Journ. Acad. Nat. Sci. Phibulel[)hia, [2] vol. ix. (1884-93) 
p. 1<)1. 
