PLATE XV 
Isotelus brachycephalus sp. nov. A cast showing the upper suHace of an 
entire individual, in a remarkably good state of preservation; figure reduced 
in size. Found in the upper or Blanchester division of the Waynesville member 
of the Richmond, about 2| miles northeast of Oregonia, Ohio, on Roaring Run, 
by Dr. George M. Austin. 
