PLATE 83 



n U 



Tylostoma mammosum. North Dakota [upper left] Wisconsin [upper right] 

 Tylostoma floridanum. Type [center leftl 



Tylostoma Berkeleyii. Folly Is., S. C, and Wilmington, N. C. [center right] 

 Tylostoma campestre. Colorado, Canada and Wisconsin [left to right below] 



