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Cytase in "Wheat Grains. 



By Katherine Golden Bitting. 



The presence of cytase was tested on sections of the wheat grain, 

 the petiole of the water lily, Nymphae odoratu, and the stem of the castor 

 bean, Ricinus communis. The cells of the endosperm of the grain were 

 so full of starch granules that the changes in the walls were difficult to 

 see. In the other sections there is considerable coUenchyma developed, 

 which is very clear and distinct, and any changes in its structure are 

 easily followed. The extracts from the ungerminated grain, and from 

 three to six days germinations were the ones which gave the most satis- 

 factory results. 



The first tests were made using hollow chambers in slides, so that 

 the changes might be followed under the microscope. These proved un- 

 satisfactory as the section went to the bottom of the chamber and only 

 the low poAvers could be used. Preparation dishes were then used, 5 

 cubic centimeters of the extract being used and chloroform for an anti- 

 septic, with the sections immersed. A control was also kept, using dis- 

 tilled water instead of an extract. After three days the following changes 

 were noted: 

 Water Lily Extract, ungerminated seeds — 



CoUenchyma. Thickened walls much swollen, middle lamella distinct, 

 like a bright thread through thickening. 



Parenchyma. Walls swollen, middle lamella distinct, intercellular 

 spaces nearly obliterated. 



Xylem. No change. 

 Water Lily Extract, three days germination — 



CoUenchyma. Thickened walls nearly lill cavity of cells, cavities 

 showing as narrow canals. 



Parenchyma. Walls swollen. 



Xylem. No change. 

 Water Lily Extract, six days germination — 



CoUenchyma. Structureless mass, separate cells indistinguishable. 



Parenchyma. Cells entirely separated, middle lamella gone. 



