THE ANCESTRY OF THE HORSE. 703 



convolutions. But this is a matter of time, for specimens are not very readily 

 obtained. The Hindoo coolies, who form the bulk of the population in the tea- 

 districts of Cachar, will never kill a Hoolock. The Kuki tribes in the Cachar 

 Hills, on the other hand, kill and eat them, and regard them as somewhat of a 

 delicacy, I believe. But even a Kuki finds it difficult to get a shot at these 

 creatures, so shy are they and so active in their movements. 



(The above appeared in the Proceedings of the Zoological Society ff London in 



Vol. I of 1903.) 



THE ANCESTRY OF THE HORSE. 

 As is mentioned in Sir W. H. Flower's well-known work on the horse, it has 

 been urged that none of the modern representatives of the Equidae can be 

 descended from the three-toed hipparions of the later Tertiary period, owing to 

 the circumstance that they lack any trace of the face-gland, or tear-gland, the 

 cavity for the reception of which forms such a conspicuous feature on each side 

 of the skulls of the latter. Many years ago Professor Huxley pointed out that 

 the fossil horses of the Siwalik Hills in India, such as Equus sivalensis, do show a 

 distinct vestige of the depression of the gland in question, remarking at the same 

 time that they are the only species of Equus in which such a vestige is visible. 

 This would be a prima facie presumption that these extinct Indian horses are 

 the descendants of the three-toed hipparions, of which numerous remains occur 

 in the same formation. 



Recently, while arranging a series of specimens in the Natural History 

 Museum, I have detected a very distinct vestige of the cavity for the face-gland 

 in the skull of an Indian domesticated horse sent home so long ago as 1845 by 

 Mr. Brian Hodgson. The depression in this skull, which is now exhibited in the 

 museum, stands out in striking contrast to the unbroken, flat, or rather slightly 

 convex, surface of the portion of the skull immediately in front of the eye-skull 

 in the case of other horses, asses, and zebras. It is, however, very remarkable 

 that a distinct, although somewhat less deep, vestige of the gland cavity is 

 noticeable in the skull of the race-horse Bend Or. It may be added that none 

 of the skulls of horses from the brickearths and turbaries of this country 

 preserved in the museum show any trace of the gland cavity. 



Premising that I much desire the opportunity of seeing other skulls of Indian 

 domesticated horses, and also those of Arabs, I think the following suggestions 

 are justified from the facts at hand : Firstly, the extinct Equus sivalensis of 

 India is descended from the three-toed hipparion of the same country, and that 

 in turn it, or a nearly allied species, has been the ancestral stock (at any rate in 

 part) of some of the Eastern breeds of domesticated horses from which our own 

 thoroughbreds are descended, this theory receiving support from the occurrence 

 of a rudiment of the face-gland cavity, not only in the skull of Mr. Hodgson's 

 Indian horse, but also in that of Bend Or. 



On the other hand, the cold-blooded horses of Western Europe are the 

 descendants of a species which had lost all trace of the face-glands of the 

 hipparion, and which was therefore widely different from Equus sivalensis. If 



