SIWALIK SELENODONT SUINA, ETC. 
15—156 
America. Its range in time is from the upper eocene (5th tertiary stage of Gaudry) 
to the lower miocene in Europe, while in India it survived (probably) to the earlier 
pliooene. Its maximum of development in Europe occurred in the lower miocene 
(8th tertiary stage.) In America it seems to be confined to the miocene. 
Number of species. — There is very great difficulty in arriving at a satisfactory 
conclusion as to the number of species of the genus, owing to the numerous 
synonyms, and the confusion caused by writers wrongly identifying new forms with 
previously described species. Dr. H. Filhol, in his memoir on the fossil mammals of 
Konzon, 1 has endeavoured to correct the synonomy of the French and English 
species, and comes to the conclusion that they should all be referred to four species, 
which he respectively terms — (l) Ancodus velaunus Pomel, (2) A. leptorhynchus Pomel, 
(3) A. bovinus Owen, and (4) A. porcinus Gervais. In the first species he includes 
the English Hyopotamus vectianus of Professor Owen, and in the second Ancodus 
aymardi of M. Pomel, the skull of which is figured under the latter name on plate XYI 
of his memoir, but which on page 188 of the same is shown to belong probably to a 
female of A. leptorhynchus. Thus far Dr. Filhol is clear enough, but on page 99 he 
observes “ that the Ancodus velaunus of M. Pomel does not correspond to Bothriodon 
velaunus of M. Aymard, as one might at first suppose, but to Bothriodon platyrhynchus 
of the same author; and that the Ancodus aymardi of M. Pomel is the Bothriodon 
velaunus of M. Aymard.” This may shortly be expressed as follows, viz .: — 
A. velaunus. Pom.=i?. platyrhynchus . Aym. 
And B. velaunus. Pvym.—A. aymardi Pomel. 
On page 186, it is stated that u the animals described under the names Ancodus 
incertus Pomel, Hyopotamus borbonicus Gervais, Ancodus aymardi Pomel, and 
Bothriodon velaunus Aymard form one and the same species.” On page 189 H. 
borbonicus is classed as a synonym of A. velaunus Pomel, and as it was before 
considered to be the same as A. aymardi Pomel, it follows that A. aymardi Pomel is 
the same as A. velaunus Pomel, and consequently that the latter is the same as 
Bothriodon velaunus of M. Aymard, which we were expressly told at first was not the 
case. In respect of these species M. Filhol has, indeed, made the 1 confusion worse 
confounded,’ and without the whole series of type specimens for comparison it is 
quite impossible to give a correct list of the synonomy and number of the species. 
The following list must, therefore, only be considered as an approximation to 
the truth ; the hypothetical reference of the form known as Hyopotamus aymardi to 
H. leptorhynchus is indicated by a note of interrogation ; and also that of H. vectianus 
of Owen to H. velaunum. The European species additional to the four French and 
English species admitted by M. Filhol are given on the authority of Dr. Kowalevsky. 
II. borbonicus is identified with II. vectianus , whether or not the latter species is the 
same as H. velaunus. 
1 l«e. eit. reprint, p. 189. 
