494 
AMERICAN JOURNAL OF BOTANY 
[Vol. 8, 
at once to a pale amber. The boiled controls did not reduce the perman- 
ganate. This is not necessarily indicative of enzyme action. The reduction 
may be brought about by substances produced by the decomposition of 
the pollen grains. 
Tests for Nuclease 
Tests for phosphoric acid, which might indicate the splitting of nucleic 
acid, were made with ammonium molybdate on ground, unground, germi- 
nated, and boiled Easter lily pollen. All showed a strong phosphoric acid 
test so that no conclusions could be drawn. 
Tests for Tyrosinase 
A solution of tyrosin gave a negative reaction for all pollens of the first 
series tested. 
Tests for Laccase 
An alcoholic solution of gum guiacum, which was rapidly colored blue 
by freshly cut potato or orange peel, gave negative results with ten varieties 
of pollen. 
Tests for Cjrtase 
1. The method given by Crabill and Reed was used. Filter paper is 
dipped in manganese sulphate solution and then in potassium permanganate 
solution. The resulting manganic oxid colors the paper dark brown. Acids 
formed by the cellulose destruction combine with the manganic oxid to 
form light-colored salts which show by contrast on the brown background. 
Both ground and unground pollen placed on moistened sterilized strips of 
such paper caused no color change, although a subsequent growth of mold 
did so. 
2. Cellulose was prepared from filter paper in the following manner. 
Schweitzer's reagent (ammoniacal cupric oxid) was used as a solvent. This 
was made by adding to a strong copper sulphate solution, first, ammonium 
chloride, and then an excess of sodium hydroxid. The blue-green precipitate 
thus formed was allowed to settle, the liquid decanted off, and the precipitate 
washed repeatedly with water on a Buchner funnel and filtered by suction. 
The precipitate was then dissolved in 0.92 percent ammonia. The resulting 
deep blue liquid readily dissolves strips of filter paper. When sufficient 
paper had been dissolved to make a thick, syrupy liquid, it was poured into 
dilute hydrochloric acid (i : 5) and the cellulose was precipitated in small 
flecks. The precipitated cellulose was washed repeatedly with water on a 
Buchner funnel and filtered by suction, until the filtrate showed no trace 
of HCl when tested with AgNOs. The pure white mass of cellulose was 
then boiled with distilled water to make a fine suspension and to sterilize it. 
The suspension was tested with both iodine and Benedict's solution to be 
sure that it was both starch- and sugar-free, as was the case. The tests 
were made as follows: 10 cc. of cellulose suspension, 100 mg. of ground 
