CHAPTER, VII 
LEONTINIDAE 
Tus family was established to include a group of large, 
heavily built ungulates, not unlike rhinoceroses in form, 
which have rooted teeth, the molars being similar to those 
of Rhinchippidae, 2. e., composed of a wall and an anterior 
and posterior lobes, but with the cristae either lacking or 
little developed; and with the second upper, and the third 
lower incisors developed into tush-like caniniform teeth. 
Two genera are especially abundant, Leontinia of the Des- 
eado beds, and Colpodon of the Colpodon beds, the former 
with the formula 374<, the latter with -({4., In many 
ways, the family suggests Nesodontidae, and undoubtedly 
belongs to that series, if not directly ancestral. The lower 
molars are distinctly of the same type as in all the other 
toxodonts, but show a tendency to become hyposodont. 
The following genera have been assigned by Ameghino 
to the family. Some of them are based on very scant mate- 
rial and I have ventured to suggest in each case what dis- 
position I have felt to be the proper one. 
Leontinia, the type genus, is described in detail on pages 
109-115. 
Scaphops is based on a mandibular symphysis, which is 
wider than usual for Leontinia, and on a second upper 
incisor which is compressed. The species in the genus 
Leontinia show a marked degree of variability, and I can 
see in this only individual variability, so that I place Scap- 
hops under Leontinia and S. grypus, as a synonym of L. 
gaudryt. 
Steniogenium is based on a mandibular symphysis with 
roots only of the teeth. The incisors are proclivous and 
inc. 3 small. I consider this also as Leontinia, and the 
species S. sclerops as a synonym of L. oxyrhynea, which I 
think is the female of L. gaudryt. 
