Haacke 229 



of the germ cells with the other cells of the body. The 

 body represents a system in equilibrium; if this changes 

 the germ cells developing in it change also. But the 

 equilibrium of the system constituted by the body becomes 

 directly altered by the acquisition of new characters; con- 

 sequently the changes which it undergoes must be trans- 

 mitted also to the germ cells. But no matter whether the 

 germ cells become changed as a result of the acquisition 

 of new characters by the body which surrounds them, or 

 whether they remain unchanged, they always inherit the 

 same thing, namely, the capacity to form that body with 

 which they were in equilibrium." 174 



Like Spencer he supposes that this equilibrium is due 

 to the tendency possessed by an infinite number of par- 

 ticles, identical throughout the whole organism, to dis- 

 pose themselves in this way only. His rhomboidal 

 gemmes, grouped into composite units or gemmaria, are 

 fundamentally nothing else than the physiological units 

 of Spencer. The geometric form attributed to them, 

 which emphasizes the static character of this explanation, 

 does not make it in any way more acceptable. 



Nevertheless there are to be noted and carefully con- 

 sidered, here perhaps, even more than in Spencer, the 

 close interaction and the reciprocal equilibrating influence, 

 which would always exist between the soma and the germ 

 substance, that is to say, between the organism and that 

 small portion of its units contained in the reproductive 

 cells, not only throughout the whole development of the 

 individual but also after the completion of development 

 when the organism becomes subject to the modifications 

 which external agents induce in it. 



174 Haacke: Kritische Beitrage zur Theorie der Vererbung und 

 Formbildung. Biol. Centralbl., Bd. XV. 1895. P. 568. 



