May 17, 1901. ] 
account for vital phenomena have been 
directed to the vital mechanism to the ex- 
clusion of the material substratum. 
Indeed, it is not an uncommon thing to 
see the argument advanced that on account 
of their instability we can never hope to 
learn very much concerning the chemistry 
of those substances entering immediately 
into the composition of the living cell, for 
the reason that any attempt at their isola- 
tion from the cell contents at once results in 
their decomposition or permanent altera- 
tion. And yet the fact remains that even 
now at least fifty apparently distinct and 
different substances are known apart from, 
and independent of, the cell, which, in addi- 
tion to some peculiar and characteristic 
property, such as the power to convert 
starch into sugar or split a fat into glycerin 
anda fatty acid, possess many of the more 
general properties and activities of the cell 
itself. These substances are the soluble fer- 
ments. In two very recent communica- 
tions on the subject Bokorny* has given 
us some additional evidence of the sensi- 
tiveness of the enzymes and some additional 
reasons for believing in the inherent simi- 
larity between these substances and proto- 
plasm. According to Bokorny, the sensi- 
tiveness of the ferments and their general 
similarity to protoplasm are to be observed 
in their conduct towards heat, light and 
the protoplasmic poisons.. He therefore 
reaches the conclusion that the enzymes are 
substances similar to protoplasmic albumen, 
and that in all probability the two are only 
to be distinguished by the fact that the 
enzymes are wanting in organization. As 
the result of some recent work on certain 
aspects of enzyme action, the writer has 
been brought to see the necessity of these 
or similar conclusions from a somewhat in- 
dependent standpoint ; and, aside from their 
extreme instability and their delicate sensi- 
* Chem. Ztg., 24, 1113-1114, Dec. 19, 1900; Chem. 
Ztg., 25, 1136-1138, Dec. 26, 1900. 
SCIENCE. 
767 
tiveness to their physical environment and 
to chemical reagents, the conclusion that 
the enzymes are active, in the sense of re- 
taining certain of the vital activities of the 
living cell, would seem to derive consider- 
able support from the following considera- 
tions : 
First, their widespread and 
occurrence in all living things. 
Secondly, their importance and necessity 
in metabolism. 
Thirdly, their mode of origin. 
Finally, in what follows it will be pointed 
out that the ferments exhibit a remarkably 
close analogy to the living non-nucleated 
fragments of the cell. 
Since the discovery of diastase, in 1814, 
a large number of enzymes have been recog- 
nized, and what is of still greater interest 
and physiological significance, a large num- 
ber of them, such as diastase, lipase, tryp- 
sin, etc., etc., have been found in both the 
vegetable and the animal organism, and, for 
that matter, in nearly every living cell. 
By means of diastase, starch is rendered 
available as a food-stuff both to the animal 
and to the plant. Trypsin occurs not only 
in the digestive fluids of the intestines, but is 
also found in the pineapple and the leaves 
and sap of the Carica papaya. The fat-split- 
ting enzyme has been found not only in 
the pancreatic secretion, but also in the 
blood and liver and in nearly every organ 
and tissue of the hog. Its presence also 
has been proved in many seeds and seed- 
lings. Myrosin, the mustard ferment, is 
found not only in the many species and 
varieties of Cruciferze, but in many other 
natural orders of plants as well. Emulsin 
is another enzyme of the widest distribu- 
tion in the vegetable kingdom. It has been 
aptly said, therefore, concerning the occur- 
rence of the enzymes, that ‘ wherever life 
exists there also occurs the enzyme.’ ‘The 
one is the inseparable companion of the 
other. It is in connection with growth 
universal 
