1914] 
DUGGAR AND DAVIS—FUCUS VESICULOSUS 423 
in the controls was obtained, and certainly no pentosanase active 
on this material could be assumed to occur abundantly in Fucus 
tissues. 
Only one series of tests has been made to identify cellulase 
in the material here reported upon, and the results are presented 
with much reserve. Precipitated cellulose, prepared from filter 
paper, was employed, and the experiments were conducted at 
40° C. The indications were that slight cellulase activity may 
occur. 
By means of the action of the alcohol-acetone preparation 
upon a 4 per cent olive oil-casein emulsion, the lipolytic activity 
was investigated in the usual way. With the emulsion used 
alcohol is most serviceable as a preservative. In the tests 
referred to there was no indication of hydrolysis after one week; 
so the preparations were permitted to stand for two months, 
but still without change. That the conditions in the above 
case were otherwise favorable for lipolytic action is shown by the 
fact that the same substrate yielded with an alga of another 
family a decidedly positive test in two days. Several series of 
experiments were likewise carried out for the determination of 
esterases. With methyl acetate, ethyl acetate, and ethyl buty- 
rate the Fucus material produced no change, irrespective of the 
concentrations employed. 
In some of our preliminary experiments it had appeared that 
urease was present, but a careful investigation of this point 
demonstrated an error in the earlier results, and no amidases 
were discovered through the action upon 0.5 per cent solutions 
of urea, acetamid, methylamine, asparagin, diphenylamine, and 
acetanilid. In these experiments NH; determinations were 
made according to the method of Folin. 
No liquefaction of gelatin or of agar occurred during a ten-day 
interval in a large series of test-tubes arranged with these two 
substrates. In the different tests these media were made 
neutral, alkaline, and slightly acid. In the neutral and slightly 
acid tubes no observable change occurred; but in those tubes 
containing a higher percentage of acid — both in those contain- 
ing the Fucus preparation and in the controls — general lique- 
faction occurred. It is obvious, therefore, that these gel- 
forming proteins are not noticeably affected by any enzymes 
