September i, 1923] 



NATURE 



127 



Baluchitherium osborni and its Relations. 



By C. 



THE history of the discovery of the various frag- 

 ments of Baluchitherium, which have enabled 

 Prof. Osborn to make the preliminary restoration here 

 reproduced (Fig. 5)/ is interesting. In 1910 the present 

 writer was fortunate enough to obtain bones of numer- 

 ous extinct animals in the early Miocene deposits of 

 Baluchistan. Nearly all of the animals were strange 

 and, except for such of them as had previously been 



FORSTER-COOPER. 



into a pair of stout, downwardly turned tusks (Fig. 2). 

 Neither skulls nor jaws appeared to be of sufficient 

 size to belong to the animal which possessed the atlas. 

 In fact, the former animal appeared to be nearly twice 

 the size, and on these grounds separate genera were 

 made, Baluchitherium for the larger form and Para- 

 ceratherium for the smaller. 



A few years later the Russian palaeontologist 

 Borissiak discovered the remains of a very similar 

 large animal in Turkestan, which he named Indri- 

 cotherium, but he likewise failed to get the skull. 

 This regrettable lacuna in our knowledge has within 

 the last few years been filled by the discovery of a 

 nearly complete skull in Mongolia, a discovery which 

 we owe to Granger, of the American Museum of Natural 



Fig. I. — Atlas of Baluchitherium with one of a modem rhinoceros. 



obtained by Dr. Pilgrim of the Indian Geological 

 Survey, were previously unknown. Among them an 

 atlas, the first bone of the neck (Fig. i) and an as- 

 tragalus, one of the principal bones of the ankle, were 

 of such astounding size as to proclaim themselves as 

 belonging to an entirely new form of mammals, and 

 one larger even than the elephant. Beyond the fact 

 that the bones belonged to the Perissodactyla, a group 

 which includes the horses, tapirs, and rhinoceroses, 

 together with some extinct families, nothing further 

 at the time could be said of them. 



Fig. 2. — Lower jaws of Paraceratherium, showing the unusual feature, 

 for a rhinoceros, of procumbent lower tusks. The length of the actual 

 specimen is 30 inches. 



During an expedition to the same place in the follow- 

 ing year further remains were obtained, which com- 

 prised other vertebrjE, limb and foot l)ones of this 

 large animal, together with teeth of a large but primi- 

 tive rhinoceros, some fairly complete skulls, and a 

 lower jaw of a size to correspond with the skulls. The 

 lower jaws, although obviously belonging to a rhinoceros 

 t some sort, and one of considerable size, showed a 

 unique feature in that the two front teeth were modified 



' Prof. H. F. Osbom in Natural Hislory, vol. xxiii. (New York), gives 

 an excellent and fully illustrated account of Baluchitherium and its relations 

 to other rhinoceroses. There is also a figure of the skull found in Mongolia. 



NO. 2809, VOL. 112] 



Fig. 3. — Femur and humerus of Baluchitherium. 



History's expedition to China. This skull is five feet 

 in length, and thus all requirements as to size are 

 abundantly filled, and with it enough bones from 

 Baluchistan, Turkestan, and China (the wide separation 

 of these areas shows the great range of distribution 

 of the animal in former times) are known to enable 

 us to make an approximate restoration, and to give 

 us a reasonable idea of what the animal looked like 

 while still alive. 



Baluchitherium on reconstruction proves to be a 

 very strange animal. The limbs are as large as those 

 of an elephant, and in some points are not unlike them 

 (Fig. 3). The feet, however, are entirely different in 

 structure, the fingers and toes, of which there are only 

 three to each foot, are much flattened, while the meta- 

 carpals and tarsals are enormously elongated (Fig. 4), 

 so much so that the wrist is elevated nearly a yard 

 above the ground, three times as high as the corre- 

 sponding measurements in the elephant. Of the three 

 toes, the central one is much the largest, the two 

 lateral ones being pressed close to its sides, rather like 

 the splint bones of the horse, though here the side toes 

 are complete. There are some very curious, and as 

 yet not fully understood resemblances to the horse in 



