EXPLANATION OF PLATE 16. 



Pelvic arch (Jamptosaunis incdiufi Marsh. No. 1880, Yale Museum. Holotype. 

 About one-fourth iiat. size. Viewed from the right side: a, acetabulum; il, 

 ilium; is, ischium; /j, pubis; p' , postpubis. From a photograph. 



324 



1 



