PLATE 4 



EXPLANATION OF FIGURES 



27 Metaphase from ileum (region 4). G and H are two sections of the same 

 cell. When superimposed, 42 chromosomes may be counted. This number 

 is possibly due to irregularity in time of division. 



28 Metaphase from ileum (region 4). 12 chromosomes. 



29 Prophase from ileum (region 5). 6 chromosomes. 



30 Metaphase from ileum (region 5). 18 chromosomes, only 17 show in 

 drawing. Figures 27, 28, 29, 30 show loss of typical size relations between cyto- 

 some and chromatin mass. 



31 Anaphase from Dr. Stevens' slide. 12 pairs chromosomes. Note two 

 lagging chromosomes. 



32 Early anaphase from colon (region 2) 6 pairs chromosomes. These 

 chromosomes seem to be smaller than those of other regions drawn. 



33 Diagram of alimentary tract of pupa showing regions included in sec- 

 tions studied. 1, rectum; 2, colon; 3, 4, 5, ileum; 5, region of entrance of Mal- 

 pighian tubules into gut; 6, 7, 8, .9, 10, stomach in abdominal region. 



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