5 1 2 Notes. 
ments made during the present summer on the occurrence of diastase 
in pollen. 
The experiments so far are only preliminary, but they establish the 
existence of the ferment in the pollen of Liliurn , Helianthus , Gladiolus , 
Anemone , Antirrhinum , and Pelargonium . The method of prepara- 
tion was to collect the pollen from freshly dehisced anthers, and to 
grind it up carefully between plates of glass with a little water or 
dilute glycerine until the microscope showed the grains disintegrated. 
So prepared it was mixed with very dilute starch-paste, containing 
about i% of starch. Half the mixture was then boiled for a short 
time and both the boiled and the unboiled halves were set aside at a 
temperature of about 20*23°C. After a few hours traces of diastatic 
action became evident. The unboiled tube lost its opalescence, and 
the addition of iodine to samples taken from it at intervals showed 
the starch undergoing the ordinary stages of conversion into dextrin 
and sugar. Simultaneously with the changes indicated by the iodine, 
the use of Fehling’s fluid showed a continuous accumulation of grape- 
sugar, the reduction of the copper oxide becoming more and more 
marked as time went on. The boiled controls showed no change. 
The blue colour on the addition of iodine remained constant and no 
copper-oxide-reducing body was formed. 
Further experiments showed that the diastatic power was not 
associated with the protoplasm of the disintegrated pollen-grain. The 
contents of several anthers of the Lily were ground up with diluted 
glycerine, allowed to stand for some hours and then filtered. The 
solution so made was clear, transparent, and free from the debris of 
the pollen. This solution when mixed with the same starch-paste 
caused it to go through the same series of changes, soluble starch, 
dextrin, and sugar, appearing as the action went on. As in the former 
case the activity of this extract was destroyed by boiling. We find 
consequently that the pollen-grains of many plants contain diastase 
which can be extracted from them as readily as from other parts of 
the plant. 
Further experiments are in progress, which will deal with the 
nitrogenous and fatty reserve materials, and with the power of 
the pollen-tube to avail itself of the nutriment obtainable from 
the tissue of the style as germination proceeds through its later 
stages. 
J. R. GREEN, London. 
