PLATE 2 



EXPLANATION OF FIGURES 



10 and 11 Early prophases from cephalic part stomach (region 10) showing 

 threads shortening, straightening and thickening. The lower group of figure 



10 shows the ends of chromosomes lying to the left. Both figures show early 

 division of the thread. The two groups of long chromosomes, L and M, in figure 



11 have straightened, while the group of short chromosomes is still folded. 



12 Early prophase from ileum (region 4) showing threads in three groups 

 surrounded by nuclear membrane. 



13, 14, 15, and 16 Early prophases showing chromatin collecting in granules 

 as the threads shorten. From stomach (region 10). Figure 13 shows two sec- 

 tions of the same cell, A and B in one, C, D, E, and F in the other. 



17, 18, 19 Prophases. Figures 17 and 18, stomach. Figure 19 ileum. Fig- 

 ures 17 and 19 show three groups of six chromosomes each. The small group in 

 each case suggests the derivation of six instead of four or eight through longitu- 

 dinal division of the original short bivalent chromosome. In figure 17, A and 

 B, C and D probablj' represent the completed division of two chromosomes 

 corresponding to E and F which are still elongated and have not completed the 

 division. In figure 19, A and B, D and E, probably represent the same condition 

 and the larger groups in this cell also show such an early division of one chromo- 

 some of each pair. Figure 18 shows a group of eighteen chromosomes, of which 

 two are nearly divided. 



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