South Dakota School of Mines 121 



who first described the species stated that he had seen hundreds 

 of shells but no skull. Even today there is record of only two 

 skulls. One of these in the Carnegie Museum of Pittsburg is 

 accompanied by the shell (see Figure 19). The other is in the 

 Princeton Museum but the body to which it belonged was not 

 found. This general absence of the head is due perhaps to the 

 fact that Stylemys was a dry land tortoise and any freshet that 

 might be able to carry or roll the heavy decaying body into water 

 where deposition was taking place would wrench the head away. 

 This, separated from the body, would be inconspicuous and hence 

 fail of ready detection. 



Several fossil turtle eggs have been found in the Badlands 

 and they are regarded as belonging to the common species just 

 described. Hay states that they are slightly elongated but he 

 indicates that this is perhaps due to deformation by pressure 

 from an original globular form. They are a little less than two 

 inches in diameter. They were formerly in the James Hall 

 collection but are now in the American Museum of Natural 

 History. 



LIZARDS. 



But few remains of lizards have been found within the 

 badland formations. Cope in 1873 described Aciprion formosum 

 from fragmentary material and in 1882 the Princeton expedition 

 found a lower jaw of the same species. Dr. George Bauer 

 briefly described two other species in the American Naturalist 

 in 1893. These are Rhineura hatched and Hyporhina antigua. 

 No figures were given. In 1901 Mr. O. A. Peterson of the 

 Carnegie Museum found two nearly complete skulls of Rhineura 

 katcheri and a fragment of a third on Badland Creek, Sioux 

 County, northwestern Nebraska. Mr. Earl Douglass described 

 and figured the two better preserved skulls in 1908 in the Annals 

 of the Carnegie Museum. The full length of the head is little 

 more than one-half inch. An enlarged side view of one of these 

 is given in Figure 20. 



Figure 20— Head of Rhineura hatcheri, enlarged nearly four times. Al- 

 ter Douglass, 1908. 



