20 Scientific Proceedings, Royal Dublin Society. 



The osazone crystals produced by the Polytrichum solution consisted of a 

 very few typical hexose tufts, and a great number of hedgehog-like crystal- 

 line groups, which, it seems likely, are largely, if not altogether, composed of 

 maltosazone ; this view is supported by the fact that when pure maltose is 

 added to the solution, there results a large addition of these crystals. They 

 are fairly soluble in hot water, and have often been found thrown down from 

 apparently pure maltose solutions, but in a mixed hexose-maltose solution it 

 often seems as though the two types (viz., glucosazone and maltosazone) 

 graded into one another. From the presence of hexose osazones in the 

 incubated solution we may infer the presence of diastase and maltase in the 

 leaves of P. commune. 



Maltose. 



In the detection of maltase the same precautionary measures were taken. 



Two grams of the powdered leaf were added to 80 c.c. of a 0'38 per cent, 

 solution of maltose. After forty-eight hours' incubation at 38°, both flasks 

 were examined for reducing sugars. 



50 c.c. of unboiled solution reduced, - 35 g. CuO. 

 50 c.c. of boiled solution reduced, 0-29 g. Cu O. 



The above figures indicate the presence of an enzyme capable of converting 

 maltose into glucose. 



The presence of maltase in P. commune is most interesting ; its distribution 

 among the vascular plants has not yet been widely demonstrated. Brown 

 and Morris' failure to find it in the leaves of Tropaeolum may be due to the 

 fact that in that plant maltose is translocated from the leaves, so that maltase 

 would not be required till the sugar has arrived at its destination. 



B. Quantitative Work. 



METHOD OF ESTIMATION. 



The fresh material is immediately immersed in alcohol, and boiled for ten 

 minutes to destroy the enzymes. 



A small quantity of calcium carbonate is added to prevent inversion by 

 the acids of the plant. 



After twenty-four hours' extraction the alcohol is decanted off. and to the 

 moss is added cold distilled water. 



After a further twenty-four hours' extraction this aqueous extract is 

 added to the alcoholic extract. The residue is washed with warm alcohol, 

 which in due course is added to the previous extracts. 



A further extraction is found to contain neither sucrose nor reducing 

 sugars. 



