Nov. 6,1916 
Grain of the Tobacco Leaf 
287 
tinue during fermentation. A microscopically visible change consists 
of a more or less complete aggregation of the grain-forming substance 
of all the cells into certain groups of cells. The factors determining the 
location of these groups are unknown. 
(8) In the tobacco studied a correlation was found between the grain 
and burning properties. It is believed that the substances contained 
in the grain bodies are injurious to the burn and that the quality of the 
latter is dependent upon the degree to which the former are aggregated 
into definite bodies sufficiently separated, one from the other, to permit 
a considerable fire-carrying zone of cells, emptied of grain material, 
around each. The influence of the degree of aggregation of the grain 
substance upon the color, texture, and elasticity of the leaf has not yet 
been thoroughly investigated. 
LITERATURE CITED 
(1) Behrens, Johannes. 
1894. Weitere Beitr&ge zur Kenntnis der Tabakpflanze. V. Der anatomische 
Ban nnd die Bestandteile des Tabakblatts in ihrer Beziehung zur Brenn- 
barkeit. In Landw, Vers. Stat., Bd. 43, p. 271-301. 
(2) Borodin, Johann, 
1878. Ueber die physiologische Rolle und die Verbreitung des Asparagins im 
Pflanzenreiche. In Bot. Ztg., Jahrg. 36, No. 51, p. 801-816; No. 52, p. 
817-831. 
(3) Garner, W. W. 
1907. The relation of the composition of the leaf to the burning qualities of tobacco. 
U. S. Dept. Agr. Bur. Plant Indus. Bui. 105, 25 p. 
(4) Hayes, H. K., East, E. M., and Beinhart, E. G. 
1913. Tobacco breeding in Connecticut. Conn. Agr. Exp. Sta. Bui. 176, 68 p., 
12 pi. _ 
(5) LoEw, Oscar. 
1900. Physiological studies of Connecticut leaf tobacco. U. S. Dept. Agr. Rpt. 
65. 57 P- 
( 6 ) SCHEOESING. 
i860. Chimie appliqu6e a la vegetation.—Nouvelles recherches sur le tabac. 
In Compt. Rend. Acad. Sci. [Paris], t. 50, no. 13, p. 642-644. 
(7) Sturgis, W. C. 
1900. On the so-called grain” of wrapper tobacco. In Conn. Agr. Exp. Sta. 
23d Ann. Rpt., 1899, p. 262-264, pi. 2. 
(8) Tunmann, Otto. 
1913. Pflanzenmikrochemie ... 631 p., illus. Berlin. 
