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along with the ripe kernel. When the oat grain is planted in the soil 
and germinates, the same conditions that cause the seed to grow, start 
the spores into activity. 
Spores have been germinated on the slides provided. Carefully cover 
the drop of water containing the germinated spores, and examine. OB- 
SERVE :— 
6. The rather long hyaline germtube or promycelium,—the 
basidium of this basidiomycete. 
7. That it is septate; number of cells into which it is divided; 
the crack in the chlamydospore-wall where the promycelium emerges. 
8. That from each cell at the septum (above or below?) arises 
one or more oblong sporidia,—the basidiospores. 
9. The variations from the normal germination. 
Make prawincs to show germination of chlamydospores and formation 
of sporidia, with such variations as are observed. 
10. Examine the mount of germinated spores to see if you 
can find any of the sporidia germinating. DRAW. 
As the seedling bursts through the seed-coat and pushes up through the 
hull, it is penetrated by the germtubes of the sporidia. The mycelium 
of the parasite grows and branches, pushing its way upward between the 
cells of the host as the culms of the oat come out and shoot upward. 
Usually every culm in the stool is infested. The mycelium at first stimu- 
lates the growth of the plant. The activities of the mycelium continue 
throughout the growth and development of the host until the formation 
of the flowers begins. In these rapidly developing embryonic tissues, 
the mycelium takes possession, appropriates the abundant food-substances 
and begins the formation of chlamydospores. The formation of these 
chlamydospores takes place as follows:—The mycelium in the flower 
at the time that spore-formation begins shows a nodulate appearance 
and the branches are closely fasicled like clusters of grapes. Within each 
swollen part of the mycelium a chlamydospore is formed. As the chla- 
mydospores mature, the encompassing walls of the parent-hyphae and 
much of the general mycelium which is not differentiated into spores, 
gelatinizes or otherwise breaks away and the spores are set free in large 
masses. 
Practically all the floral parts of every spikelet are destroyed, trans- 
forming them into the black sori of the pathogene. The smutted panicles 
emerge, the spore-masses ripen, and the spores are scattered when the 
healthy panicles are in full bloom. 
REPORT 
1. Write a concise explanation of why the formaldehyde- 
treatment succeeds with loose smut of oats and fails with loose smut of 
wheat. 
