DIGESTIVE ENZYMES IN POIKILOTHERMAL VERTEBRATES 
193 
amount in animals such as the bull snake, whose diet consists almost wholly of 
animal food. 
Table 8.- — Amylase 
[50 c. c. digests were used containing boiled starch to 1 per cent and toluol to 5 per cent of total volume. Controls contain boUed 
extract. Id iodine test, — = blue, no color change; + = some color change (reddish or brownish); ++ = colorless, no starch.] 
Description 
C. c. 
of ex- 
tract 
Milligrams glucose per c. c. 
digest 
Days 
Net gain 
Days 
Iodine test 
at end of 
experiment 
Intestine: 
Carpi- 
Section 1_ - control.. 
Section 1 - experiment. 
Section 2 -do... 
Section3 - do... 
Section* -do... 
Carp, middle of intestine {eipfrtaent: 
Sucker, anterior third of in-lcontrol 
testine \experiment. 
Necturus. 
/control 
"\experiment._ 
Bull snake teknE: 
f control . 
snapping turtle Sr"'" 
Caeca: Crappie. 
lexperiment. 
/control 
"(experiment. 
1.11 
1.11 
1.11 
1.11 
1. U 
1. 15 
1. 15 
1. 11 
1. a 
1.08 
1.08 
1. 02 
1. 02 
1.00 
1.00 
1. 11 
1. 11 
1.36 
1. 36 
1. 11 
2.44 
2.00 
1. 36 
1. 15 
2.38 
1. 11 
1. 47 
1.00 
2. 38 
1. 11 
2.86 
1. 36 
2.27 
1. 11 
3.85 
3.12 
2.38 
2.94 
1. 15 
2. 86 
1. 11 
2. 17 
1.08 
2. 56 
1.02 
1.39 
1.00 
3. 33 
1. 11 
4. 76 
4. 35 
3. 33 
3.23 
1. 15 
3. 57 
1. 11 
2.78 
0. 00 
1. 33 
.00 
1.23 
.00 
.36 
1.36 
2.78 
1.02 
2.08 
1.00 
4.00 
1. 11 
5.55 
1. 36 
3. 85 
.00 
1.38 
.00 
1.75 
.00 
.91 
0. 00 
2. 74 
2.01 
1. 27 
1.83 
.00 
1.71 
.00 
1.06 
.00 
1. 48 
.00 
.37 
.00 
2. 33 
.00 
0. 00 
3. 65 
3. 24 
2. 22 
2. 01 
.00 
2.42 
.00 
1. 67 
.00 
1. 42 
1.06 
.00 
3.00 
.00 
4.44 
.00 
2.49 
1 Equal length sections, anterior to posterior, of entire alimentary tract. 
With the exception of the pickerel, in which the pancreas is not well defined, all 
pancreatic digests produced exceedingly rapid digestion (Table 9). In nearly all 
cases 2 c. c. of extract converted 50 c. c. of 1 per cent starch solution to reducing sugar 
within one day, and the greater part of it was reduced within a few minutes or hours. 
The iodine tests likewise indicated rapid disappearance of the starch, generally 
becoming colorless within a few hours. With 0.5 c. c. of extract of carp hepato- 
pancreas in 50 c. c. of 1 per cent starch, the iodine test indicated the total disappear- 
ance of starch, and Benedict's sugar test indicated an increase in reducing sugar 
of 5.57 to 6.17 milligrams per cubic centimeter in four hours (Table 10). With the 
same amount of extract of turtle pancreas per 50 c. c. digest the iodine starch 
test was almost colorless, and the reducing sugar was increased 5.15 milhgrams per 
cubic centimeter in one hour (Table 11). In order to determine if amylase from the 
turtle's pancreas acted upon starch more rapidly at 37° C. than at room tempera- 
ture, 1 c. c. of extract diluted 10 times was used in 50 c. c. of 1 per cent solution, 
which would be the equivalent of extract from 1 gram of tissue to 4,000 c. c. of 1 
per cent starch (Table 12). In one hour the digest at 24° C. had gained 2.01 
milligrams of glucose per cubic centimeter, while the other at 37° C. had gained 
2.22 milligrams of glucose per cubic centimeter, indicating more rapid digestion 
at 37° C. 
