38 
We notice from these figures not only an enormous increase of /- 
catalase, but also a considerable increase of a-catalase. It had been 
observed twice before by the writer that the a-catalase also was 
increased in the sweated sample as compared with the cured sample. 
He ascribed this circumstance to accidental differences in the leaf 
character. But this supposition has to be abandoned in view of the 
above figures obtained from average samples. The only explanation 
the writer can offer that seems probable is, that there exists in the case 
of catalase, as with many other enzyms, a zymogen in the leaves, which, 
under the conditions brought about in the sweating process, is con- 
verted into the a-catalase enzym itself.! 
The relative intensity of the fermentation, or sweating, has also a 
decided influence upon the amount of 4-catalase. Thus, upper leaves 
moderately sweated for wrapper purposes contain less than upper 
leaves heavily sweated for filler purposes. The amount of oxygen devel- 
oped in thirty minutes by /-catalase was observed with the sample 
of the former to be 186 ¢. ¢., of the latter, however, 236 c. c. (both of the 
same crop). The difference in the amount of oxygen developed in 
thirty minutes in both cases by a-catalase was but small, 619 and 
634 c. c. oxygen, respectively. 
In order to decide whether the petuning liquid’ which was applied 
for the filler leaves, but not for the wrapper leaves, had contributed 
to the increase of the amount of catalase, 20¢. ce. of that liquid were, 
after neutralization, mixed with 20 c. c. of water and 5 ¢c. c. commercial 
hydrogen peroxide. The total amount of oxygen developed. in thirty 
minutes was but 26 ¢.c. Since the amount of the petuning liquid 
applied was only 0.66 per cent of the weight of the tobacco, not more 
than 0.02 ¢.c. of oxygen gas would have been developed in thirty min- 
utes by the amount of petune contained in 2 grams of tobacco applied 
for the test on catalase, an amount so small that it can be neglected. 
DEVELOPMENT OF THE “GRAIN” OF THE TOBACCO LEAF. 
The *‘ grain” means to the tobacco manufacturer small points plainly 
visible on the extended leaves after the curing or after the sweating 
process. These points, often situated at the base of the hairs, appear 
under the magnifying glass as small globules of yellowish color, show- 
ing sometimes a radiated structure. Boiling with water or with dilute 
acetic acid does not remove them, but treatment with dilute hydro- 
chloric acid does so at once. This makes it very probable that the chief 
mass of these globules consisted of calcium oxalate, a view confirmed 
by the microscopical observation of gypsum needles forming under the 
''The writer holds as probable that while a-catalase may be generated from a 
zymogen, /-catalase is produced from a-catalase only, and not from a separate 
zymogen. > 
>This liquid was prepared from licorice and various condiments, with addition of 
some rum, according to the prescription given by Marcus L. Floyd in Report No. 62, 
U.S. Department of Agriculture, p. 19, Cultivation of Cigar Leaf Tobacco in Florida. 
tira. 
