6 BULLETIN 109, U. S. DEPARTMENT OF AGRICULTURE. 



leaf, it appeared probable, in view of the fact that the infection 

 was introduced with the tragacanth paste, that the growth on the 

 cigar was confined to the paste present on the wrapper. It was 

 thought desirable to try to check up this conclusion by attempting 

 to grow these molds on cigars. Accordingly, repeated attempts were 

 made to grow the organisms in question on pieces of cigars moistened 

 and placed in sterile Petri dishes or test tubes. In some cases these 

 pieces molded and in others they did not. Usually the piece at the 

 head of the cigar molded without difficulty, while those portions from 

 other parts of the cigar molded less readily. 



This seemed to confirm the view that the molds were introduced 

 with and in general grew on the paste, and the appearance of the 

 mold over a large part of the surface of a cigar indicated the smear- 

 ing of excess paste- over a corresponding portion of the surface. 



REMEDIAL MEASURES. 



Having located the cause of the trouble in the organisms above 

 discussed and having found the point of their entrance, as well as 

 the seat of their activities, to be in the tragacanth paste, practical 

 remedial measures seemed to lie along the line of sterilizing the 

 paste. 



In view of the conditions governing the subsequent handling and 

 final utilization of cigars, an acceptable sterilizing agency must 

 combine several characteristics. It must be permanent, since cigars 

 sterilized for but a short time are liable to mold at a later period 

 when conditions of heat and moisture concur with or follow the 

 exposure of the cigars to the infecting organisms. The substance 

 must be odorless and tasteless; otherwise it will alter the taste and 

 aroma of the cigar, points on which smokers, and therefore dealers, 

 are very sensitive. It must not alter the color or the luster of the 

 wrapper, since on these the selling quality of the cigars in consider- 

 able part depends. 



STERILIZATION OF THE PASTE. 



A variety of substances having antiseptic properties were chosen 

 for test. In general they were dissolved in water, and the resulting 

 solutions were either added to the paste already made or were used 

 instead of water in making up the paste. These pastes were then 

 inoculated with the molds obtained from the moldy cigars or from 

 tragacanth gum. 



A thin paste containing 10 grams of gum in 1 liter of water was 

 first used. Hydroquinone, thymol, and sodium salicylate were intro- 

 duced in concentrations as strong as could be used without influ- 

 encing in an objectionable degree the taste, color, or odor. These 

 pastes were then inoculated with Aspergillus candidus and Peni- 

 cilliurn glsmcwm. In all cultures except that containing 5 c. c. of 



