STAUKASTRUM. 167 



processes, whose apices are rounded, bearing two small di- 

 verging aculei ; end view triangular, sides concave, angles 

 broadly truncate and produced into two processes with a 

 wide, rounded sinus between, a third process from a position 

 somewhat back of the sinus, rising at an angle of about 40 

 degrees, projects between the other two, thus constituting 

 three divergent processes at each of the angles of the triangle. 

 Diameter, including the aculei, 30-38 yu. 



Collected by Ed. Potts in Harvey Lake, near Wilkes-Barre, 

 Pa., where it appeared in numbers. 



The three diverging, aculei-tipped processes at each angle 

 make this form a distinct species. 



