EXPLANATION OF PLATE 9. 



Omphalosaurus nevadanus, n. gen. and sp. Inferior view of a portion of the 

 mandible with two vertebrae and several elements from the palatal 

 region. A, angular; Sp, splenial; Pt, pterygoid; PI, palatine; V, 

 vertebrae. Middle Triassic, South Pork of American Canon, West 

 Humboldt Range, Nevada. X 



