PLATE 3 
A. —Part of section of a young sorus on leaf stalk. Peridial cells fully elongated at 
the right, contents disappearing, intercalary cells collapsing. 
B. —Part of section of a small and rather flat sorus on a cane. Buffer tissue of erect 
cells; intercalary cells in all stages of disorganization. Five uredospores at right 
center. 
