SPECULATIONS REGARDING THEM 255 



cyte would look like when it divided, for no one had 

 ever seen a division in a leucocyte. These peculiar 

 cells are large, and easily examined. They differ from 

 all other cells in that they contain a polylobed 

 nucleus, and it was very difficult to imagine how 

 mitosis would occur in such a cell. Speculations have 

 been made from time to time to the effect that these 

 cells divide by pluripolar mitosis. Each lobe of the 

 nucleus is said to undergo a mitosis of its own, and 

 that the chromatin within the lobe forms up into 

 chromosomes. This would mean that a cell with five 

 lobes to its nucleus would divide into ten cells. Such 

 a speculation makes no allowance for the Altmann's 

 granules, which attain a large size in these cells, or 

 for the filaments which unite the several lobes of the 

 nucleus. Since the cytological process of mitosis in 

 lymphocytes was so different to what was expected, 

 we were prepared to see the speculation disproved; but 

 in spite of this it must be admitted that when at last 

 the divisions of leucocytes were seen the arrangement 

 of their cytological elements came rather as a reve- 

 lation. 



Jelly-films were made which contained greater 

 strengths of the azur dye, extracted from polychrome 

 stain in the way which we have described. The 

 possibility of divisions being induced in leucocytes 

 was considered to be an event which would be seen 

 before long; but when it was first seen it, like the 

 first mitosis in lymphocytes, was not recognized or 

 appreciated. The increased quantity of azur dye was 

 added to the jelly in reality to see what the effect of 



