104 The Badlands Formations of the Black Hills Region 



lower jaws. Elotherium is the best known genus, its skeleton 

 being represented by considerable material. Marsh and Scott 

 have each published restorations of this animal, and Scott has 

 described its various structural features in much detail.* Of 

 the ancestral peccaries (Tagassuidae) Desmathyus (Thinohy- 

 us.)j is best known. Peterson has described specimens of these 

 from northwestern Nebraska.''' 



Elotherium was evidently a very grotesque animal (see 

 Plates 41 and 42). Considered as indirectly ancestral to present 

 day swine, it nevertheless showed few of the distinct suilline 

 characters. In not a few respects it resembled the hippopotamus. 

 Its size varied considerably, ranging in some species to near the 

 size of the present day rhinoceros, the head alone reaching some- 

 times more than three feet in length. Dinohyns hollandi, a, nearly 

 related genus, had a sjkull whose length, according to Peterson, 

 reached more than thirty-five inches.* The Elothere skull is re- 

 markable in many ways. The muzzle is long and slender, the eyes 

 shifted far back, the cranium short, brain cavity absurdly small, 

 the sagittal crest high and thin and the zygomatic arches enor- 

 mously developed. Other odd features are the pendent compress- 

 ed plates given off from the ventral surface of the jugals and two 

 pairs of knob-like processes on the ventral borders of the lower 

 jaw. In young individuals the knob-like processes are only 

 rough elevations, in some adults, especially the smaller species, 

 they are little more than rounded knobs, but in the larger forms 

 they become greatly elongated and club-shaped. Their use 

 seems to be wholly unknown. The dentition above and below on 

 each side is as follows : incisors, three ; canines, one ; pre-molars, 

 four; molars, three; total, forty- four. The canines, both above 

 and below, are large and powerful. They do not appear to be 

 of any sexual significance as the females developed them as fully 

 as the males. Their use seems to have been that of digging up 

 roots, in view of the fact that certain well preserved specimens 

 show deep grooves on the posterior side of the lower teeth near 



♦Marsh, O. C. Restoration of Elotherium. Am. Jour. Sci., Vol. 

 47, 189 4, pp. 407-408. 1 pil. 



Scott, W. B. The Osteology of Elotherium. Trans. Am. Philos. 

 Soc, Vol. 19, 1898, pp. 273-324. 2 pis. 



t Peterson, O. A. New Suilline Remains from the Miocene of 

 Nebraska. Mem. Carnegie Mus., Vol. 2, 1906, pp. 305-324, 2 plis. 



tFor a recent careful description of Dinohyus hollandi including excel- 

 lent restorations of the skeleton and of the animal in life, see the following: 

 Peterson, O. A., A Revision of the Entelodontidae. Mem. Carnegie Mus. 

 vol. 4, 1909, pp. 41-156, pis. 54-62. 



