The Terms of Bioplustology. — Hyatt. 295 
by the more direct demonstration of experimentation, is the 
physical forces of the surroundings. These certainly have 
the power to originate modifications either through their as- 
sumed direct action upon the growth of the parts, or through 
their power to excite internal reactions and consequent mod- 
ifications of parts and organs. 
It is certainly not a very acute analysis of the facts which 
attributes to external causes exclusive power in producing 
modifications in many case-, as has been largely done by ex- 
perimental zoologists. For example, Brauer and the author 
have both pointed out this defect in the accepted explana- 
tions of the famous Schmankewitsch experiments upon 
Arternia, and the same maybe 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 pas- 
sive 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 insep- 
arable association with consciousness, and I have suggested 
entergogenesis, entergogenism. and entergogenie from evTo;. 
within, and spyov, work or energy. 
The physical forces of the surroundings must act through 
medium of entergogenie movements and this is shown clearly 
in the nature of modifications produced which are extra 
growths, substitutions or 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 superimposed 
characteristics as in accelerated development. 
Ctetology should also, however, include the study of the ac- 
tion 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 entergogenie reactions without danger or confusion. 
Maupas gives exceedingly instructive examples of this 
elass and quotes other authorities who have investigated 
these effects in Protozoa. 
Beddard gives a number of example- <>l' such modifications 
in his "Animal Coloration'* and Semper has also discussed the 
