GENERAL REMARKS. 



685 



differs greatly from the horse in its teeth, and by the fact 

 that it possessed a deep depression in front of each eye, in 

 which depression was lodged a large tear or scent gland, 

 similar to that found in several kinds of deer and antelope. 

 Had the H. gracile been in the genealogical line we are 



Fig. 640. — Front view of near fore 

 leg of horse, below the fore-arm 

 (^ actual length). 



considering, this depression would not be entirely absent 

 in the horse ; because the upper Miocene and Lower 

 Pliocene ages, during which this three-toed Hipparion 

 lived, are not very remote periods, from a geological 

 point of view. The H. gracile was between 13 and 14 

 hands high. Von Zittel (Handbuch der Palaontologie) gives 



