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healthy plant provided. Rub the healthy leaf between thumb and fingers 
and touch the broken leaf-stub with the finger. LABEL. 
These plants will be kept in the greenhouse and are to be examined every 
two days for two weeks. Make notes on the first appearance of the dis- 
ease, i. e. (a) the number of days since inoculation; (b) the maturity of 
the infected leaves; (c) whether or not inoculated piants show infection. 
After two weeks, the plants will be returned to the laboratory for final 
notes. At this time a tabulation-sheet of the results recorded will be made 
to obtain the class-result on the different types of inoculation. 
REPORT 
1. Give the class-record of the inoculation-experiments. 
2. State the various ways that the virus can be disseminated. 
What precautions should be taken to prevent dissemination. Explain. 
