ad 
t~ 
17,4 Lee: Fungicides and the Citrus-canker Organism 329 
fore, 1 to 300 seems to be the most dilute solution ponsible. for 
this disinfectant. 
TABLE 3.—Results of exposures with 3-day-old culture of Pseudomonas 
citri in dilutions of Liquor cresolis compositus. 
Dilution. 
1to|1to|1to|1to|1to|1to|1to|1to|1to 
Exposure. 400. | 300. | 200. | 100. | 600. | 500. | 400. | 300. | 200. 
Tested, February 7, v, 
1920; observed, Feb- | Tested, April 28, 1920; ob- 
ruary 10, 1920. served, April 30, 1920. 
Min. sec. 
2 0) +} —-}-fpoptt ttt pete 
6 oOo; —jJ—-}]—-}—-} +] 4+y7—-1-]- 
7 3}/—|;—-}/—-i—t]+}]—-]-}]-]- 
Ee a ee eT ee de 
12 30; — _ — — _ _ ne ing ss 
16 00; — _ _ _ — pe ie isd ome 
The kerosene emulsion, the tests of which are reported in 
Table 4, is a mixture suggested by previous experience for 
possible use as a disinfectant in canker-control work, also operat- 
‘ing as a contact insecticide against scale insects which often 
become serious on citrus trees following copper sprays. The 
stock emulsion was prepared by adding 3 parts of kerosene to 1 
of Liquor cresolis compositus. Ina 1 to 50 mixture of this stock 
solution with water, the Liquor cresolis compositus would then 
be at a dilution of 1 to 200 parts of water. 
TABLE 4.—Results of exposures with 3-day-old culture of Pseudomonas 
citri in dilutions of kerosene stock emulsion. 
[Date of test, February 5, 1920; date of observation, February 8, 1920.] 
Dilution. 
Exposure. 
1to|1to}1to| 1 to|1to}| 1 to; 1 to! 1 to}; 1 to} 1 to 
90. | 85. | 80. | 75. | 70. | 65. | 60. | 656. | 50. | 46. 
Min. sec. 
2° w| + oe = 3g mW + ga oe ties = 1 be 
5 w+ 83 + = 8 + - _- —_— | — - 
(Be A eo + + et “ ae _ _ 
20 002 = — ie oe pe a Bee, tgwces eas 2 
122- Dy Pe ae _ ~~ o — 525) ee ee 
i 15 00; — _ - ae _ — |e ~ _ ~_ 
® Tube tested for P. citri, February 7; positive for P. citri, February 8. 
b Tube tested for P. citri, February 7; negative for P. citri, February 8. 
¢ Tube tested for P. citri, February 8; negative for P. citri, February 11. 
