18i8.] 49 



considerably more developed, so as to present the appearance of an almost dis- 

 tinct 'Tonical column. 



Opposite the interlobular depression of the last molar, the exterior demicones 

 combine to form a strong and much projecting, triangular, vertical ridge, the 

 base of the triangle corresponding to the base of the crown. A similar ridge, 

 though not quite so prominent, exists at the antero-external angle of the antero- 

 external demicone. These ridges probably also existed in the penultimate molar, 

 which is not capable of being determined from the imperfi ction of the s[iecimen. 



These teeth differ from the molar tooth of the Merycopotamus, figured in 

 Owen's Odontography,* by being much smaller, the ridge along the base of the 

 iimer demicones being neither so strong nor rugged, in the projection of the ena- 

 mel fold on the crown separating the antero-internal, from the postero-external 

 demicone, by the presence of the two strongly prominent external ridges, and the 

 absence or very slight development of the convex ridge at the bottom of the ex- 

 ternal concavities. 



The inferior molars, in general appearance resemble tho^e of Dichobune, Cuv. 



The exterior demicones are a little longer and about as broad as the interior 

 superior ones, and their external prismatic surface is not so much inclined. At 

 their base, on the front and back of the teeth, there exists a ridge corresponding 

 in its characters to that of the superior internal demicones. Between the two 

 demicones at their base, exists a triangular tubercle, apparently produced by the 

 union of the basial ridges of the demicones at this point. 'J he supero-internal 

 face is concave, but does not descend so much as the correspomling surface of the 

 supero-internal demicones. 



The points of the inner demicones, when compared with the exterior ones, rise 

 higher than the corresponding or exterior demicones of the superior teeth. 



Their external surface is compressedly triangularornearly convex, and nearly 

 vertical. Internally they are more oblique, concave from side to side, but ele- 

 vated into a broad convex ridge in the middle. The posterior angle has the ap- 

 pearance of being slightly twisted inwards, so as to produce a small prominence. 

 Below the posterior prominent angle of the antero-internal demicone, and pro- 

 jecting from the base of the posterior demicone, is a small tubercle that looks as 

 if squeezed in the angle of separation between the demicones. 



In the specimen, the posterior molar has but two lobes, which if it be the nor- 

 mal condition, would be a remarkable peculiarity among the ruminantoid Pachy- 

 dermata. A third lobe might have existed which has been broken off, although 

 the tooth has no appearance of such a loss. 



The breadth of the lower jaw, below" the penultimate molar, is about equal 

 to that of Cervus virginianus, and internally, just above th? base and parallel to 

 it, it is deeply depressed. The species I have named " Culbertsonii," in honor 

 of the family, to vphom science is indebted for the preservation of these interest- 

 ing remains. 



Measureme7its.-]^ 

 Superior molars : — , 



Penultimate : 



Greatest heighth of crown, at exterior demicones, ... .5 



* Owen's Odontography, Vol. 1, p. 566. 



t The measurements are taken in English inches and parts of ditto. 



