[Vou. 2 
808 ANNALS OF THE MISSOURI BOTANICAL GARDEN 
to a lesser extent. Glycogen, which is very generally 
hydrolysed by diastase, is here decidedly less readily attacked 
than the other polysaccharides. This would seem to indicate 
that we are dealing with a distinct enzyme, one that might be 
placed in the same category with dextrinases. These latter 
always occur with the diastases but are held by many workers 
to be distinct. 
Some of the substrates tested for hydrolysis do not, as far 
as we know, occur in the plants investigated. This is true of 
sucrose, lactose, and inulin. However, although this might 
reconcile us to the failure to find their specific enzymes, it does 
not argue conclusively against such enzymes being formed. It 
is well known that tissues do form ferments that have no de- 
tectable substrates upon which to act—the rennen of the 
bird’s stomach and the urease of the Soja bean being notable 
examples. Inulin, as pointed out previously, does occur in 
certain ‘‘greens,’’ as in Acetabularia and members of the 
Dasycladaceae. Unfortunately, none of these forms were 
available for investigation. 
The absence of lactase and sucrase is not so significant as 
is that of maltase. It is very generally considered that in the 
plant, as well as in the animal organism, poly- and disac- 
charides must be hydrolysed to simple sugars before assimila- 
tion can take place. It is hardly possible that the algae are an 
exception to this general rule and yet it is difficult to account 
for this important negative result. It is known that inhibit- 
ing agents do not affect all enzymes alike, and it may be here 
that if such agents are liberated on the death of the cell, the 
maltase might prove more sensitive to them than the other 
carbohydrate enzymes. According to the findings of Kylin 
(713), both dextrose and fructose have been demonstrated in 
the tissues of Ascophyllum, Fucus, and Laminaria, but in ex- 
tremely small quantities. These results would tend to con- 
vince one that an enzyme giving rise to them is probably 
present in the algal cell. 
Such carbohydrates as galactans, pentosans, and mannans, 
are very frequently met with in the algae and are potentially 
capable of being split to assimilable sugars. That they are 
