224 DIVISIONS INDUCED IN LYMPHOCYTES 



lymphocytes and cancer-cells forming the chromo- 

 somes, we thought that these granules were composed 

 of chromatin, but that Altmann's granules as ex- 

 emplified in polynuclear leucocytes were of quite a 

 different nature. As will be shown later, the granules 

 of leucocytes also form the chromosomes in the same 

 way as those of lymphocytes and cancer-cells. Professor 

 Lorraine Smith suggested that the apparent absence of 

 granules in lymphocytes and cancer-cells might be due 

 to the fixative, and he is right. The cytoplasm of every 

 living lymphocyte is full of minute granules which stain 

 like chromatin with aniline dyes, and these granules 

 clump together to form the chromosomes during cell- 

 division a point about which there can be no question 

 whatever. 



In some other cells, such as some large cells of the 

 liver, we have seen large granules in the cytoplasm (as 

 well as fat globules), which will not stain. What their 

 function is we do not know, for we have not been able 

 to induce divisions in these cells. The granules of 

 lymphocytes we shall henceforth style "chromosome- 

 granules," the nucleolus as the "nucleolus-centrosome," 

 and the nucleus as the "nucleus-spindle." 



