[Vou. 2 
800 ANNALS OF THE MISSOURI BOTANICAL GARDEN 
It diffused readily in water with no resulting viscosity. Ten 
ec. of the ‘‘diffusion-extract’’ were used for enzyme action, 
toluene added, and the flasks kept at a temperature of 21-23°C. 
for 100 days. The data here obtained are given in table vim. 
Dextrin here more nearly approaches starch as a favorable 
substrate, differing from the action evidenced by the other 
algae with the exception of Lammaria, where all action was 
slow. There is also a slightly increased action over that evi- 
denced by Rhodymenia, for all the carbohydrates hydrolysed. 
THE CARBOHYDRASES OF CERAMIUM RUBRUM 
As was the case with Rhodymenia, it was necessary here 
to use 20 volumes of the water-extracting medium, not, how- 
ever, because of the great viscosity, but on account of the 
great adsorption of water by the tissue particles. The alcohol 
precipitate was copious and finely flocculent. It diffused in 
water rather slowly, giving a mixture that was only slightly 
viscous. Ten ce. of the ‘‘diffusion-extract’’ were used for 
action, the usual percentage of toluene added, and the flasks 
maintained at a temperature of 21-23°C. for 100 days. The 
data are given in table rx. 
TABLE IX 
THE ACTION OF A “DIFFUSION-EXTRACT” FROM FRESH CERAMIUM TISSUE UPON 
CERTAIN CARBOHYDRATES 
Sugar as glucose in 5 cc. 
Substrate mgms. 
15 days 45 days 75 days 100 days 
Starchipeae sy teers tere 6.85 Sep nS) 16.9 
Dextiritiaem erecta 1S 15.0 il7/ 55) 19.6 
Glycogen jaccrncr steelers rs Trace 6.2 3 8.85 
[Waminiariniecc ice dace tho?! 9.4 1251 112.2 
JGayed boat. waren oadion oS eee oie Trace Trace 
SUCKOSC scene die see ene Trace Trace Trace 
WWaAGCEOSe Aarens ere re se Trace 
IMaltoseaceceme eaeee Trace Trace Trace 
Dextrin proved the most favorable substrate for the carbo- 
hydrate enzymes of this alga, the hydrolysis being about the 
same as that evidenced by Agardhiella. With the exception 
of glycogen, the other carbohydrates showed a decreased 
hydrolysis when compared with this latter form, and when 
