1915] 
DAVIS—ENZYME ACTION IN MARINE ALGAE 797 
portions being removed and sugar determinations made at 
the definite intervals noted in table v. 
The carbohydrases in this form appear to be limited to those 
acting on starch and dextrin, and with these the hydrolysis 
proceeds much more slowly than was true with either of the 
preceding ‘‘greens.’’ The lower temperature at which the 
hydrolysis occurred does not explain completely the lessened 
action. Inhibiting substances or else an actually smaller con- 
centration of the enzyme seem to be important factors. 
TABLE V 
THE ACTION OF A “DIFFUSION-EXTRACT” FROM AIR-DRIED LAMINARIA TISSUE 
UPON CERTAIN CARBOHYDRATES 
Sugar as glucose in 5 cc. 
mgms. 
Substrate 
Another series (table vr) of flasks was set up with the same 
form, using a ‘‘diffusion-extract’’ from the fresh tissue. Ten 
ce. of this diffusion represented 6 grams of the Laminaria 
pulp. In addition to the usual substrates, .5 per cent lamin- 
arin was used. Toluene was added and the flasks maintained 
for 60 days at room temperature (22-23°C.). 
TABLE VI 
THE ACTION OF A*DIFFUSION-EXTRACT” FROM FRESH LAMINARIA TISSUE UPON 
CERTAIN CARBOHYDRATES 
Sugar as glucose in 5 cc. 
Substrate 
