INTRODUCTION 5 



which the splint-bones of the modern horse are an 

 interesting survival. 



From the carvings left by the Cave-dvi^ellers, the 

 Hipparion had already assumed a horse-like form ; but 

 even then there appears to have been a cleavage into 

 two types, the one resembling the modern wild horse of 

 the Gobi Desert, coarse in its head, inelegant in its neck, 

 with a low-carried tail ; while the other was of a more 

 slender make, with a narrower, more tapering head, 

 which undoubtedly signified " quality," as understood by 

 horsemen at the present time. It is more than probable 

 that this was the " old original " of the Arabian horse 

 and the Barb, which conclusion is strengthened by the 

 hollow depression in the skull, in front of the orbit, 

 being common to both Hipparion and Arabian horses, and 



Fig. 1. Fig. 2. Fig. 3. 



their descendants, even when crossed with other breeds. 

 Moreover, it is entirely wanting in the skulls of the wild 

 Mongolian horse, as well as in those of the horses of 

 Northern Europe, such as the Iceland and Norwegian 

 ponies, and the coarse-bred horse of the common type 

 (the Shire horse alone excepted), more especially in those 

 breeds where a dun colour prevails. This cavity is pre- 

 sumed to have contained a gland, such as is possessed 

 by antelopes and deer, which secretes a fluid that is 

 supposed to give out a special odour, by which indi- 

 viduals of a tribe may track each other if they happen 

 to be separated and scattered. Sach cavities in front of 

 the eye can be traced in our thoroughbred horses, due 

 to the introduction of the blood of Eastern horses into 

 our indigenous racing stock. Professor Cosser Ewart 

 has stated his opinion that in the Early Eocene Period 



