» If the resting stage had been included in the cycle considered, 

 . . No- cells in a given mitotic stage ^^^ ^^^ ^^^^,.^^ ^^ ,^^ ,0 ^^j,^^ 3,3^^3 ^.^ ,^,3 ,g3,i,g ^^^^^ 



bage n ex ^b. .) ^^ ^^ ^ mitotically active cells (i. e., excepting the rated at unity, A. R. D. of the resting stage=.6612 and A. R. D. of 



resting cells) observed in the same fields. all 10 active stages =.3388. 



There is no systematic procession of a recognizable S. I. through the succes- 

 sive mitotic stages during the definite time periods. 



If there were fair constancy of duration of the several mitotic stages, and If 

 there were a rhythmic fluctuation in the Mitotic Index^then the Stage Index 

 procession would be quite pronounced; provided the duration of the severa l 

 stafres were equal. Hence the necessity of converting the several Stage 

 Indices into indices which would have appeared had all stages been of equal 

 duration. The Procession Index (P. I.) does this. 



• ■ Connects highest S. I. of each stage. 

 ■ Connects lowest -S. I. of each stage. 



