194. THE THEORIES OF EVOLUTION 



pose that variations are only a manifestation of the 

 energy of the germ plasm comhined with the influence 

 of the environment. 2 The latter hypothesis seems to 

 be the rational one, for the germ plasm is not inde- 

 pendent anatomically nor physiologically from the 

 rest of the organism, and besides, to admit the appear- 

 ance of variations without cause would be as absurd as 

 to admit the possibility of spontaneous generation. 



All variations are therefore acquired, and we are 

 not justified in designating exclusively as acquired 

 those which appear at a later period of the individual's 

 life and whose appearance we can personally observe. 



Le Dantec, a Neo-Lamarckian, gives a definition 

 of acquired characters which makes the discussion of 

 their hereditary transmission apparently useless. 



"By acquired characters we must only designate 

 definitive variations which do not disappear with the 

 cause that produces them. It is only in the case of 

 such truly acquired characters that it is worth while 

 finding out whether they can be transmitted by inher- 

 itance." 



These truly acquired characters never remain purely 

 local phenomena for "the organism cannot be affected 

 except by general modifications" and every local influ- 

 ence necessarily generates a certain disturbance in the 

 general equilibrium, which spreads as far as the repro- 



2Th. H. Montgomery. The Analysis of Racial Descent in Animals, 

 Chap. V: Variations and Mutations. 



