53 



The vault is convex, most venlicose on the side opposite the 

 azygous area. It is fully as large as the calyx and bears a very 

 small subcentral proboscis. It is covered with rather large, polyg- 

 onal, convex plates, and is slightly depressed in the interradial 

 reas. 



This species somewhat resembles in form, B. spergenensis, but 

 differs in the interradial and azygous areas, beside that is a 

 twenty armed species while this has only eighteen. It will not be 

 mistaken for any hitherto described. 



Found in the Warsaw group, in Washington county, Indiana, 

 and now in the collection of Wm. F. E. Gurley. 



