24 
BE. W. KOVALEVS KY ON THE 
Mauremont, described in two memoirs by Pictet, De la Harpe, and PIumbekt. Here 
the Hyopotamidoe were much more numerous than at Egerkingen, and presented a great 
variety of size. Among these remains were some specimens identical with those found 
at Egerkingen, and they were correctly referred to the Ilyopotamus Gresslyi. The 
largest species was said to be identical with Ilyopotamus crispus , Gerv. ; but as Professor 
Gekvais, in the second edition of his ‘ Paleontologie Fra^aise,’ referred the Hyo- 
potamus crispus to Xiphodon (without any suitable ground, as it seems to me), the 
whole matter must be revised once more. I cannot refrain from stating here that, in 
their second memoir, Messrs. Pictet and Humbert have mixed jaws belonging to different 
animals in a very strange manner. For instance, the upper jaw figured (l. c. plate xxiv. 
fig. 3, c ) as Bhagatherium is in reality a Hyopotamus, and the lower jaw (fig. 2) bears not 
the least resemblance to the true Bhagatherium mandible figured in the first memoir, 
and, in my opinion, belongs to Hyracotlierium or Anchilophus. In the same paper, 
moreover, the two authors have figured and described a very interesting small Paridigitate 
mammal, which they called Cainotherium Benevieri ; but there is not the slightest doubt 
that this small Ungulate cannot be referred to the genus Cainotherium. I have stated 
before that the chief characteristic distinction of the molars of Hyopotamus , as described 
by Professor Owen, consists in having five distinctly developed lobes or crescents to their 
upper molars. These five lobes or crescents are disposed transversely, three on the 
anterior half and two on the posterior half of each upper molar, as may be distinctly 
seen in Plate XXXIX. fig. 1. With the exception of Dichodon and Mery cop otamus, 
all Eocene and Miocene Paridigitata with crescentic teeth had always five lobes on their 
upper molars, disposed in the same way as in Ilyopotamus ; and, so far as we know at 
present, the position of the five cusps of the upper molars is reversed only in two very 
characteristic genera, two being placed in front and three behind. These two genera 
are Hichobune and Cainotherium , which also by their osteological characters seem to 
stand in a very near and direct relation. Every mammalogist is aware how constant are 
the dental characters in large groups of Mammalia ; and if I state that such different 
genera as Camelopardalis , Camelus , Cervus , and Bos show less amount of difference in the 
structure of their upper molars from one another * * than exists between the molars of 
Cainotherium Benevieri and the Cainotheria from Auvergne, every one will readily admit 
that the so-called Cainotherium Benevieri , in which the five cusps of the upper molars 
are disposed in the same way as in all Hyopotamoids (three in front and two behind), 
cannot be put into the same genus with the true Cainotheria , in which the disposition 
of the cusps is reversed — two in front and three behind. (Messrs. Pictet and 
Humbert noticed this difference in their description, but they did not consider it im- 
portant enough for a generic distinction.) The upper premolars show also some 
this in the present paper, as I hope to collect more ample materials, not only for the dentition, hut also the 
skeleton of the Eocene Hyopotomidce. 
* Professor Owen in Quart. Journ. Geol. Soc. vol. iv. p. 111. 
