260 Raymond FH. Pond. 
sharper end points could be obtained when ethylbutyrate was saponi- 
fied by this commercial product than when castor oil and lipase were 
used. It is much easier to obtain pure ethylbutyrate than pure castor 
oil.. For those reasons the Holadin was used. 
All of the work here presented has been done in the laboratory of 
the New York Botanical Garden, and I am indebted to this institution 
for financial support and liberal encouragement in the investigation. 
To Professor Wm. J. Gies I wish to make special acknowledgment 
for frequent and valuable counsel. 
METHODs. 
Holadin. — This substance is a commercial product prepared from 
pancreatic glands by Fairchild Brothers & Foster of New York City. 
The lipolytic activity of this preparation is regarded as relatively less 
than its proteolytic or its amylolytic power. It comes to market as a 
powder which is very hygroscopic and soon decomposes with a strong 
odor if exposed. If kept in a properly stoppered container, the lipo- 
lytic efficiency remains undiminished for a period of six months, at 
least, this being the limit of my experience. On forming a colloidal 
solution with water the reaction is at once appreciably acid if the so- 
lution is sufficiently concentrated. If 2c.c. of the filtrate obtained by 
filtering a colloidal solution containing 1 gm. of the powder in 100 
c.c. of water be added to 2 c.c. of water, it is found that about 0.30 
c.c. of M-20 KOH is required to neutralize the total volume of 4 c.c. 
After four hours’ incubation at 40 C. this initial acidity will be 
doubled. To what the initial acidity is due, or why there is an 
increase during incubation or digestion at room temperature, is not 
known. Perhaps there is some fat or other acid-yielding substance 
in the powder. Boiling inhibits the progress of acid formation during 
incubation. The initial acidity of a solution of the concentration men- 
tioned is not changed by boiling. In stronger solutions, however, 
there is possibly a slight increase in acidity due to boiling, but it is 
too slight to be accurately measured by M-20 KOH and is therefore 
negligible. 
On heating a filtered solution of 1 gm. of the powder in 100 c.c. 
of water it is noted that coagulation commences at about 60° C. Heavy 
flocculation soon occurs at higher temperature. The filtrate of this 
boiled solution contains protein substance, and gives the reaction for 
Phosphate with molybdic solution. Salts of the heavy metals will 
