364 F. B. Loom is — Origin of the Wasatch Deposits. 



them to the Placosauridse, without giving them any name. It 

 seems to me, however, that the presence of teeth on the ptery- 

 goids, the shape of the teeth on the jaws, and the osteoderms 

 would indicate rather affinity with the Lacertidse. 



The species from the Bridger are, with one exception, much 

 larger. In the present form the cylindrical teeth are attached 

 in a pleurodont manner, with about one-third of the tooth 

 above the outer margin of the jaw. The crown of each tooth 

 is slightly compressed, making a blunt edge front and back. 



Fig. 3. Glyptosaurus obtusidens. A, lower jaw, inner view ; B, the 

 same, outer view ; C, ventral shield. x3. 



!Near the base is a small opening for the blood vessels into the 

 pulp cavity, and on each alternate tooth this is enlarged by the 

 absorption which has taken place near the successional new 

 tooth. The five teeth occupy 6-| mm . An ornamented shield 

 characteristic of the genus was found near by, and probably 

 belongs to this species. It has a slight ridge along the mid- 

 dle, but is otherwise flat. The tubercles along the margin are 

 somewhat larger than those near the center. This shield 

 measures 8'7 mm long by 4 mm wide. Beside the above speci- 

 mens, a second jaw and some vertebrae were found. 



