110 THE WHITE RIVER BADLANDS 



and hind. These represent the second, third and fourth toes 

 of five-toed animals. In addition to these, a splint bone on 

 each fore foot represents the fifth toe, and a small nodule of 

 bone is recognized as being the last lingering remnant of the 

 first toe. The middle or third toe is longer and larger than 

 the lateral ones and terminates in an enlarged, somewhat 

 triangular bone, corresponding to the hoof bone of the pres- 

 ent horse. 



Among the later horses from the badland formations, 

 Neohipparion whitneyi of the Upper Miocene is noteworthy. 

 The type specimen found on Little White river by Mr. H. F. 

 Wells of the American Museum expedition in 1902, and 

 described by Mr. Gidley in 1903, is the most perfect fossil 

 horse skeleton ever discovered. (Plates 24 and 34) The 

 preservation of the skeleton is extraordinary, even the rib 

 cartilages being found in place as well as the tip of the tail. 

 The skeleton, approximately forty inches high, was that of a 

 mare, and was found in association with the incomplete 

 skeletons of five colts. It was proportioned like the Virginia 

 deer, "delicate and extremely fleet-footed, surpassing the 

 most highly bred modern race-horse in its speed mechanism, 

 and with a frame fashioned to outstrip any type of modern 

 hunting horse, if not thoroughbred." 



Notwithstanding the highly developed nature of its 

 skeleton Neohipparion represents a side branch of the horse 

 family and for some reason, like Hypohippus, the "forest 

 horse" and Parahippus, became extinct. Protohippus, an 

 animal of about the same size as Neohipparion, survived and 

 established for itself, as did the earlier Mesohippus, a de- 

 finite place in the genealogical line leading to Equus of to- 

 day. 



TITANOTHERIDAE 



The Titanotheres are the largest animals found in the 

 White River badlands. With the exception of turtles and 

 Oreodons they are also the most abundant. The family was 

 a comparatively short-lived one but it has proven to be one of 

 the most interesting known to vertebrate paleontology. 



Dr. Hiram A. Prout of St. Louis, in 1846 and 1847, 

 described briefly in the American Journal of Science a por- 

 tion of the lower jaw of one of these animals, the first speci- 

 men ever obtained from the White River badlands, and called 



