1276 
How they appear in the cell, how they behave to nucleus, chro- 
midia, ‘chromosomes, and other cell-organs, and many questions 
more, form the subject of the heredity researches of to-day, which 
however start from the supposition that the said theory is in the 
main right. Nor does the observation that heredity units or factors 
may occur in latent condition and must then be activated by special 
kinds of food, by alcalies or acids, or other stimuli, touch the fact 
of their existence. 
By the side of this view stands another, only apparently quite 
different, namely that the living’ part of the protoplasm is built up 
of a large number of various enzymes. A nearer consideration of 
these two views shows that “heredity units’ and ‘‘enzymes” means 
the same. *) 
Hence the fundamental conception here to be proposed, that every 
hereditary character of an organism corresponds to one or more 
enzymes, which exert a reaction on specific substrates. 
Long ago already I came to the conviction that the ontogenetic 
evolution of the higher plants and animals can be best explained 
by admitting that it is caused hy a series of enzymes, for the 
greater part endoenzymes, which, becoming active in a fixed succession, 
determine the morphological and physiological properties gradually 
manifest in the development. These enzymes in the formation 
of plant-galls are likewise concerned, and in a study on the 
galls of the saw-fly Nematus capreae on the leaves of Salix amyg- 
dalina, | gave them the name of “growth enzymes”) It is still my 
Allgemeine Vererbungslehre. Pag. 265, 1911. — M. W. Brwerincx, Mutation 
bei Mikroben. Folia microbiologica. Bd. 1, Pag 24, 1912. — W. JOHANNSEN, 
Elemente der exakten Erblichkeitslehre. 2nd Ed. Pag. 148, 1918. etc. 
1) Younger physiologists (as E. ABDERHALDEN, Physiologische Chemie, Ste Aufl. 
Theil 2 Pag 997, 1915) wrongly use anew the old and equivocal word “ferment”, 
instead of the practical and clear word “enzyme”. The history of the introduction 
of the word enzyme is as follows. In “Verhandlungen des Naturhistor. und Medicin. 
Vereins zu Heidelberg”, Sitzung am 4 Februar 1876, Bd. 1, N. F., the account 
of a lecture of Kiitune begins thus: “Herr W. Kürre berichtet über das Verhalten 
verschiedener organisirter und sogenannter ungeformter Fermente. Um Missverstind- 
nissen vorzubeugen und lästige Umschreibungen zu vermeiden, schlägt Vortragen- 
der vor die ungeformten oder nichtorganisirten Fermente, deren Wirkung ohne 
Anwesenheit von Organismen und ausserhalb derselben erfolgen kann als Enzyme 
zu bezeichnen”. This proposal is still acceptable. That KüranNe only thought of 
exoenzymes was in accordance with the times. The term ‘‘endoenzyme”’ was 
introduced in 1900 by M. Haun (Zeitschr. f. Biologie Bd. 40 Pag. 172, 1900). 
But the conception existed already long before. Enzyme comes from the Greek 
“en” in, and “zymè” leaven, and is related to “zeo”’ I boil. 
*) Das Cecidium von Nematus capreae auf Salix amygdalina. Botan. Zeitung, 
1888, Pag 1. 
