ON THE ELECTRICAL CHARGE OF PROTEIN. 155 



We know that the spermatozoon reacts specifically with 

 the egg, that this specificity is, however, not absolute, 

 as shown by the production of bastards. This specificity 

 can also be altered through different chemicals, as shown 

 by the remarkable hybridization experiments of LOEB. 

 We see further that the spermatozoon becomes immo- 

 bilized within the egg, in that a kind of precipitation, the 

 formation of the astrosphere, a characteristic morpho- 

 logical sign of fertilization, starts from the spermatozoon. 



Let us compare with this picture such a process as the 

 agglutination of bacteria through immune serum. Here 

 also there exists a specificity which is, however, by no 

 means absolute, and here also an immobilization in the 

 serum of the mobile bacterium. According to the 

 pleasing idea of PALTAUF, we are dealing in this case 

 with the formation of a precipitate about the capsule of 

 the bacterium, something similar, therefore, to the change 

 which occurs about the spermatozoon which has pene- 

 trated an egg. The specific effects of the immune bodies 

 can also be altered through chemicals. 



They are always associated problems, therefore, which 

 arise in this or the other illustration used, and they all 

 spring from the manifold similarity which exists between 

 the colloids of the organism within and without the cells 

 and which is determined to so great a degree by the 

 electrical properties of the colloids. 



There can be little doubt that out of the study of the 

 physico-chemical properties of the colloids there will 

 spring a new bud of physical physiology in which the 

 application of the modern teachings of electricity will 

 play a primary role. The physiology which recognizes 



