NISHIMURA: A CARRIER OF THE MOSAIC DISEASE 225 
twelve plants were kept as controls and after twenty-five days 
they were found to be free from any symptoms of mosaic. See 
TABLE II. 
TABLE II 
SUMMARY OF EXPERIMENT NO. 3 
No. erent | First symptoms a 25 days =. inocula- 
I | July 22 July 20, mosaic on the first new leaf 7 Disease developing 
2] ** * July 30, mosaic on the first new leaf | 8 eS = 
3 ‘“ “| July 28, mosaic on the first new leaf 6 as " 
OS poe leas, No reaction 
5 | ** | July 30, mosaic on the first new leaf | 8 Disease developing 
is gah | No reaction 
7 | Aug. 8) Aug. 16, mosaic on the first new leaf 8 Disease developing 
_o ehehe eee No reaction 
9 | «| Aug. 17, mosaic on the first new leaf 9 Disease developing 
ro | ‘ ‘| Aug. 15, mosaic on the first new leaf 7 * = 
ir | ‘“  ‘ Aug. 17, mosaic on the first new leaf 9 “5 SG 
12) “ “| Aug. 18, mosaic on the first new leaf | 10 2 “ 
6 A eather No reaction 
14 “| Aug. 16, mosaic on the first new leaf | 8 Disease developing 
15 | “Aug. 17, mosaic on the first new leaf | 9 a S 
16 | ae ae | ae ae ee ae oe “oe ee oe | 9 ae “ 
I7 | «| Aug. 19, mosaic on the first new leaf | II - vs 
18 | ‘“  ‘ Aug. 18, mosaic on the first new leaf _ Bae) es i 
4. Inoculation of the tobacco with juice of healthy alkekengi plants 
To prove that the juice of uninoculated plants of the alkekengi 
will not produce the disease in tobacco twelve healthy young 
N. Tabacum plants (ten- to eleven-leaf stage) were inoculated on 
September ro with the juice of the leaves of healthy P. Alkekengi 
by method No. 3, the same which was used in experiment No. 2. 
After thirty days two new leaves or more appeared on each plant 
but did not show any symptoms of the disease. 
5. Comparison of inculation periods 
To compare the length of the incubation period in my transfers 
through P. Alkekengi with the ordinary incubation period when 
tobacco is inoculated with juice from diseased tobacco, a series of 
inoculations was made using methods Nos. 4, 7, and 8; twenty . 
plants of NV. Tabacum were used in each of the three series. The 
first series were inoculated on March 28 by method No. 8, the plants 
having eight to ten leaves. The second series were inoculated 
on April 5 by method No. 7, the plants having five to seven leaves. 
