196 



WM. REES B. ROBERTSON 



TABLE XVIII 



Fat body 



27.8 

 32.6 

 37.4 

 44.2 

 68.6 

 72.8 

 47.0 



In the tables giving first spermatocyte lengths the sex chromo- 

 some appears longer than in the tables of other cells. This is 

 due to the peculiar behavior of the sex chromosome in these 

 cells, where it is relatively longer and narrower than in other 

 kinds of cells. Its length according to the diagram is therefore 

 greater than it should be. 



An examination of the tables will show considerable variation 

 in the length of each chromosome for cells of different tissues. 

 Some of this variation, no doubt, is due to faults in the measure- 

 ment or drawing of the chromosomes, as well as to cases of fore- 



