168 



PROCEEDINGS OF THE ACADEMY OF 



[1889. 



posteriorly. Pleurae grooved about half 

 their length. Pygidium triangular, axis 

 prominent and tapering to a blunt obtuse 

 point, marked with about 9 axial rings ; 

 lateral lobes with seven ribs, the first two 

 pair are grooved. 



Geol. position, Trenton group. Murfrees- 

 boro, Tennessee, also Stone River 6 miles 

 north of Murfreesboro. 



This species has some affinities with 

 Dahnanites intermedins, Walcott, from the 

 Trenton group of Wisconsin, but in minor 

 details it can readily be distinguished from 

 it. 



