IT REVEALS FALLACIES 5 



the microscope slide. By this study of vital activity 

 new lessons have been learned concerning the real 

 functions of the morphological elements of the cells. 

 For instance, owing to the fact that the older methods 

 merely showed pictures of dead cells and the arrange- 

 ment of their component parts after they are dead, 

 controversies have arisen regarding the functions of 

 the cellular elements. Unfortunately, theories regard- 

 ing these functions have sometimes become accepted 

 as facts. The "lobes of the nuclei" of leucocytes are 

 generally recognized as being analogous to the nuclei 

 of other cells, in spite of the fact that the act of cell- 

 division has never been seen in leucocytes. 1 The very t 

 designation of the cells "polymorphonuclear" is 

 even based on this theory; but in reality the "lobes 

 of the nuclei" are the centrosomes. We hear it said 

 even now that the blood-platelet is a precipitate, 

 although a single glance at a specimen in vitro, espe- 

 cially if an alkaloid is present in the jelly, demonstrates 

 beyond denial that a blood-platelet is a living creature 

 arid a highly amoeboid cell. 



The new method reveals new points in every direc- 

 tion which are difficult to reconcile with the old 

 theories based upon the examination of dead specimens, 

 some of them so firmly rooted that people may be slow 

 to discard them. 



Infinite interest and variety awaits the investigator 

 of cells by this new method. He is dealing with living 



1 Throughout this book the word "leucocyte" refers to the polymorpho- 

 nuclear cell; the mononuclear cell from the peripheral circulation is called a 

 lymphocyte. 



