NO. 2127. 



OSTEOLOGY OF THESCEL0SAVRU8—0ILM0RE. 



613 



Under the above definition were included the genera Nanosaurus, 

 Laosaurus, and Dryosaurus from America and Hypsilophodon from 

 the Wealden of the Isle of Wight. 



Evidently it is a slip of the pen that the premaxillaries are described 

 as being without teeth, for they were certainly present in the pre- 



FiG. 20.— Map SHOWING localities wheee Thescelosaueus remains have been found. (1) Nio- 

 brara County, Wyoming; (2) Deer Ears Buttes, South Dakota; (3) Hell Creek, in Mon- 

 tana. 



maxillae of Hypsilophodon (the type-genus of the family), as is 

 abundantly demonstrated by the text and illustrations of several 

 authors. 



Wliether Thescelosaurus will be found to have teeth in the pre- 

 maxiUaries is yet to be determined. It is quite probable, however, 

 that during the great time interval that had elapsed between the 



