THE NEW CELL DOCTRINE 



enties of the last 

 century J. Heitz- 

 mann, a Viennese 

 physician who had 

 emigrated to New 

 York, affirmed that 

 cells are not defi- 

 nitely separated 

 from one another. 

 He advanced the 

 statement that 

 protoplasm is con- 

 tinuous and has 

 scattered nuclei. 

 The opinions ex- 

 pressed by Heitz- 

 mann^ remained in 

 their time almost 

 without notice. 

 Very gradually his 

 view met with 

 wider acceptance. 

 The botanist Sachs 

 has contributed 

 much to develop 

 our interpretation. 

 For the zoologists 

 the writings of the 

 American Whit- 

 man^ have been of 

 the greatest im- 

 portance. Whit- 



