PLATE i 
Rubus occidental ™, black raspberry, infected with the long-cycled orange-rust. 
A. —Tip plant which was infected with sporidia of the Gymnoconia in August, 1921; 
photographed March, 1922. 
B. —Section through the cane at b in A: p, pith; x, wood ring or xylem; m, cam¬ 
bium; s, sieve tubes; b, hard bast or stereome (tissues s and b constituting the phloem) 
k, cork cambium; c, cortex; e, epidermis. Sections of the stolon at a and b in A 
showed no hyphae; midway between a and b there was an abundance of mycelium 
in the cambium and phloem, but none in the pith. Sections through the base of 
each infected shoot revealed hyphae in the pith, phloem, and cortex. See figure 1 
for further details. 
