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Scientific Proceedings.^ Royal Diihlin Society, 



nine years ago. At that time I was managing a Remount Depot in South 

 Africa during the war, where there were seldom less than two thousand 

 horses at a time. Over forty thousand horses passed through this depot in 

 the two and a half years of my management. These were, moreover, from 

 different countries of origin. 



Owing to the system on which this depot was conducted, it lent itself 

 peculiarly to the observation of horses. The horses were kept loose in large 

 enclosures provided with shelters. They were exercised by letting them 

 into a central track, about two hundred at a time, where they were allowed 

 to trot and canter round at their own will. They were watered by diverting 

 them into enclosures where water troughs had been established, and returned 

 to their enclosures to be fed after watering, the food having been put out for 

 them dui-ing their absence. By seeing horses manoeuvred in this way, it 

 was possible quickly to get to know them individually, because they all had 

 necessarily to pass a point in review many times a day at the morning and 

 evening exercise. In the interval of time between these exercises and the 

 watering and feeding, I had every day to pass many hundreds through an 

 arraugement in connexion with the tr.ack in which, in a narrow gangway, 

 they could be handled and caught, or let go, as required. It was here that I 

 had an opportunity of studying the extent of degenei'ation in different 

 breeds, and tlie variations in the skeleton which I deal with in this paper. 



Fig. I. — Limb Bones. 

 KiG. 2. — H. J. Hiji Joints 



S. J. Slioulder Joints. E. J. Elhow Joints. S. Stifles. 



A study of the skeleton of existing mammals in natural liistory collec- 

 tions, from the largest to the smallest, and of remains of extinct ones, will 

 make it clear that the bones of the limbs are roughly cylindrical, the upper 

 aud lower articular facets having the same direction (fig. 1). Since the 

 bones are also straight (fig. 1 a), it follows that the pairs of limbs lie in 

 parallel planes (fig. 2), the pairs of joints being equally wide apart, and the 

 joints of each limb in line (fig. 3 a). The only variation apparently occurs 

 ip animals of unusual strength and power. In these, tlie arms and thighs are 



