M. E. Jewell and H. B. Lewis 163 
with sand and water in a mortar. The extracts were then fil- 
tered through cotton. Extracts of the organs of the pig, sheep, 
and dog could not be made until from 12 to 24 hours after their 
removal from the body. 
The detailed results are shown in the tables. An enzyme 
capable of hydrolyzing lichenin with the formation of a reducing 
sugar was found to be present in the alimentary system of each of 
the twenty species of invertebrates examined (Table I), while in no 
case was such an enzyme observed in the alimentary tract of the 
vertebrates under investigation (Table II). In every instance the 
extracts of the vertebrate tissue were active, as evidenced by 
their strong amylolytic properties. This inactivity of extracts 
of the organs of the vertebrate alimentary system is in agree- 
ment with the limited number of observations of earlier investi- 
gators. Von Tschermak (5), however, has reported the presence 
of lichenase in the pancreas or intestine of half the number of 
normal rabbits examined in connection with his studies on adapt- 
ation of enzymes to diet. Glycerol extracts of the organs were 
used and the fermentation test was made as a criterion of the 
absence or presence of a monosaccharide after incubation of the 
. extracts of the tissue with the lichenin. Differences in tech- 
nique may account for the variations between his work and that 
of other experimenters. 
That lichenase was not uniformly distributed throughout the 
whole invertebrate organism was demonstrated by tests carried 
out on the extracts of the muscle tissue of the crayfish (Cam- 
barus virilis). Repeated examination of muscle extracts of this 
species gave no evidence of the presence of lichenase, although 
extracts of the hepatopancreas of the same individuals showed 
marked action on lichenin. It has been suggested by von Tscher- 
mak (5) that the enzymes for the hydrolysis of lichenin and 
inulin are closely associated or may even be identical (inulo- 
lichenase). The inulase of Aspergillus niger is also able to effect 
the hydrolysis of lichenin (1). In the present series of experi- 
ments there is no evidence of any close association between 
inulase and lichenase. While lichenase was found to be present 
in the alimentary tract of twenty different species, inulase was 
observed in only one instance, in the experiments with Lampsilis 
luteola. There is no apparent relationship between the occur- 
