EXPLANATION OF PLATE XXXI. 



Figs. 1-3. Vertebrae of the Liodon dyspclor from Butte Creek, one-half natural size. 

 Fig. 1. Atlas and axis from the front, the odontoid hone wanting: a, axis; 1>, neurapophysis of atlas; 

 c, basal element of atlas ; d, hypapophysis of the odontoid. 



2. Axis, posterior view. 



3. Third cervical vertebra, from behind. 



4. Six caudal vertebra) of Liodon dyspclor, consecutivo, except an interval between the third and 



fourth ; one-third natural size. Of tho anterior throe, the diapophyses of the left side are 

 broken off, and the neural spines, being turned to that side by pressure, are displayed. From 

 the specimen figured in Plates xxvii-xxx. 



5. Centrum of a lumbar vertebra of Liodon dyspclor, from behind. From the type-specimen in tho 



Museum of the Smithsonian Institution, from Fort McKae, New Mexico. 



