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“cations either through their assumed direct action upon the growth 
of the parts, or trough their power to excite internal reactions and 
consequent modifications of parts and organs. 
It is certainly not a very acute analysis of the facts which attri- 
butes to external causes exclusive power in producing modifications in 
many cases as has been largely done by experimental zoologists. For 
example, Brauer and the author have both pointed out this defect in 
the accepted explanations of the famous Schmankewitsch experi- 
ments upon Artemia, and the same may be said of the explanations 
of all experimenters who do not take into account the reactions of the 
organisms themselves. I mean here not simply the passive structural 
organization but the active internal reactions usually called effort by 
the Neo-Lamarckian school. The use of the word effort is, however, 
misleading, since it has inseparable association with consciousness, and 
I have suggested entergogenesis, entergogenism, and entergogenic 
from ‘Evroce, within and Epy6v, work or energy. 
The physical forces of the surroundings must act through medium 
of entergogenic movements and this is shown clearly in the nature of 
modifications produced which are extra growths, substitutions of 
characteristics due to changes of functions etc. or partial or absolute 
obliteration of these due to the failure of genetic force to repeat 
characteristics in the presence of opposing influences and superim- 
posed characteristics as in accelerated development. 
Ctetology should also however, include the study of the action of 
physical forces when they either actually do produce direct effects 
upon organisms or may be assumed to act in this way. Changes in 
light, food, heat and moisture may cause modifications that cannot be 
included under the head of entergogenic reactions without danger or 
confusion. 
Maupas gives exceedingly instructive examples of this class and 
quotes other authorities who have investigated these effects in Protozoa. 
Beddard gives a number of examples of such modifications in 
his »Animal Coloration« and Semper has also discussed the same 
subject more extensively in his »Natiirlichen Existenzbedingungen 
der Thiere 5.« 
The use of the term entergogenesis makes it practicable to indi- 
cate the essential distinction existing between the modifications pro- 
duced through the mediation of internal forces and those arising as 
the direct results of the action of external forces by means of the term 
ectergogenesis and ectergogenic. 
5 Translation by Minot, MacMillan, 1892. 
