A NEW FOSSIL RUMINANT GENUS. 5, 



plates of enamel have a character which distinguishes them from all known 

 ruminants : the inner crescent, instead of sweeping in a nearly simple 

 curve, runs zig-zag- wise in large sinuous flexures, somewhat resembling 

 the form in the Elasmotherium. 



The three double molars differ from each other only in their relative 

 states of wearing. The antepenultimate, being most worn, has the 

 crescentic plates less curved, more approximate and less distinct : the 

 penultimate and last molars are less worn, and have the markings more 

 distinct. 



The three anterior or simple molars have the usual form, which holds 

 in Ruminantia, a single semi-cylinder, with but one pair of crescents. The 

 first one is much worn and partly mutilated : the second is more entire, 

 having been a shorter time in use, and finely exhibits the fiexuous curves 

 in the sweep of the enamel of the inner crescent : the last one has the sim- 

 ple form of the permanent tooth which replaces the last milk molar : it also 

 shews the wavy form of the enamel. 



Regarding the position of the teeth in the jaw; the last four 

 molars, viz. the three permanent and the last of replacement, run in a 

 straight line, and on the opposite sides are parallel and equi-distant : 

 the two anterior ones are suddenly directed inwards, so as to be a good 

 deal approximated. If the two first molars were not thus inflected, the 

 opposite lines of teeth would form exactly two sides of a square : the 

 length of the line of teeth, and the intervals between the outer sur- 

 faces of the four last molars, being almost equal, viz. 9.8 and 9.9 inches 

 respectively. 



The plane of detrition of the whole series of molars from rear to front 

 is not horizontal, but in a slight curve, and directed upwards at a consider- 

 able angle with the base of the skull : so that when the head is placed, so 

 as to rest upon the occipital condyles and the last molars, a plane through 

 these points is cut by a chord along the curve of detrition of the whole 



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