THE TOXICITY TO FUNGI OF VARIOUS OILS AND SALTS. 27 



Copperized oil. 

 (PI. IV, figs. 49 to 51.) 



[Laboratory sample No. 1095. Cooperator, Ellis-Foster Co., New York, N. Y. Probably a crude petroleum 

 containing a slight amount of copper and sufficient vegetable oil to form a homogeneous solution; specific 

 gravity, 0.937 at 25° C; flash point, 125° C; burning point, 164° C; less than 0.2 per cent distills below 

 215° C; 30.2 per cent distills below 320° C; about SO per cent distills below 360° C; copper content, 0.34 

 per cent.] 





Tests. 



Times 



killing 



point 



verified. 



Concentration of the preservative 

 (per cent). 



'Fungus. 



Num- 

 ber. 



Duration. 







3 



5 



15 



30 



33 



36 



40 



Check. 





40 

 25 



Weeks. 

 4 to 9 



1 



4 

 4 



4 

 4 



3 



4 



2 



2 



2 





 4 



4 





4 to 6 



4 



















Fomes annosus: In 18 to 22 days the radial growth of the check reached 40 mm.; 

 the toxic concentrations up to 6.25 per cent showed the same growth, except that 

 the check was denser. In about three weeks 15 to 30 per cent reached 1 to 11 mm. 

 In nine weeks, 30, 33, and 36 per cent showed 12 to 20 mm. On the less toxic media 

 alternating zones of lighter superficial growth and darker submerged growth occurred. 

 On the high concentrations either a black submerged growth or a light-brown super- 

 ficial growth appeared. 



Fomes pinicola: In two weeks the radial growth of the check reached 40 mm.; 

 15 to 26 per cent, 20 to 27 mm.; 40 per cent, 2 mm. In six weeks all concentrations 

 up to 40 per cent reached about 40 mm. The growth on the toxic media was fluffy, 

 but darker than that on the check. 



None-Such Special. 

 (PI. IV, fig. 52.) 



[Laboratory sample No. 2696. Cooperator, George M. Saums Co., Trenton, N. J. Yellow, oily liquid 

 with strong varnish or paint odor; claimed by the manufacturers to waterproof and give a hard finish 

 to timber, as well as prevent or stop decay; chemical composition unknown to us.] 





Tests. 



Times 



killing 



point 



verified. 



Concentration of the preservative (per cent). 



Fungus. 



Num- 

 ber. 



Duration. 



1 



5 



15 



25 



30 



35 



40 



45 



Check. 





2S 

 29 



Weeks. 



4 



3 to 4 





4 



4 



4 



4 



4 



4 



4 

 4 



4 

 4 



4 

 4 



4 

 4 



4 



4 







4 









Fomes annosus: In 10 to 14 days the radial growth of the check reached 20 mm.; 

 concentrations from 5 to 45 per cent showed approximately 40 mm. The preservative 

 appears to exert a nutritive or stimulative effect, rather than any toxic action, although 

 the fungus will not grow on the pure preservative. The growth on the treated media is 

 dark and submerged, rising to the surface later to form a very dense creamy mycelium. 



Fomes pinicola: In eight days the radial growth of the check reached about 30 mm. ; 

 0.25 to 3 per cent, 15 to 20 mm. In two to three weeks 35 to 50 per cent showed 20 

 to 40 mm. The growth on all concentrations up to 50 per cent almost equaled that 

 on the check. 



DISCUSSION OF TESTS. 



Table II gives the results of investigations in our laboratory in 

 the use of such preservatives as have been sufficiently checked to 

 permit statements regarding their toxicity to the fungi noted under 



