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From the material of affected pines, take a bit of the peridium; stain 
with eosin and mount in water. OBSERVE :— 
24. The character of the cells of the peridium. DRAW. 
Study the sections through white pine twigs bearing aecia. NOTE:—. 
25. The position of the aecia in relation to the tissues of the twig. 
26. The stroma at the base of the aecium and the radiating 
mycelium in the host-tissue. 
27. The origin of the peridium. 
28. The sporophores each bearing a chain of aeciospores. 
DRAW in detail an aecium with the surrounding host-tissues. 
REPORT 
1. Illustrate graphically the steps in. the primary and secondary 
cycles of this pathogene. 
2. Illustrate graphically the nuclear phenomena exhibited during 
the life-history of this rust. 
