142 FERNANDUS PAYNE. 



contained the five differential chromosomes. Further study has 

 thrown very little light upon the question. Fig. 7, E. F. G and 

 H, represents its history as 'far as I have traced it. E shows it 

 shortly after synapsis ; F gives its typical apparance when the cell 

 has reached its maximum size ; G represents a stage toward the 



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FIG. 9. Gelastocoris (Galguhts) oculatus Fabr. A, metaphase figure of 

 the second division, polar view, showing the ring of 15 and the four chromo- 

 somes of the pentad group near the middle the fifth chromosome of this 

 group could not be shown, as it lies beneath the four ; B, early anaphase of 

 the second division, polar view, showing the 19 chromosomes which go to one 

 pole ; C, metaphase of the second division, side view, showing the typical 

 position and arrangement of the chromosomes of the pentad group ; D and 

 F, anaphases of the second division, side view, showing the manner of separa- 

 tion of the pentad group, four chromosomes of which go to the one pole and one 

 to the other only three chromosomes of the four group show, as all of them 

 do not lie in the same plane. The photographic enlargement is 1,500 diameters. 



end of the growth period and before the chromosomes begin to 

 form. At this time the contents are thrown out into the nucleus 

 and it is probable that the part thrown out is chromatin as it 

 appears to take part in the formation of the chromosome a little 

 later. After the contents are thrown out, the nucleolus does not 

 entirely disappear until the chromosomes are well formed (Fig. 7, 

 /). As the five differential chromosomes cannot be identified 

 before the second maturation division, it is impossible to trace 

 their earlier history with accuracy. It is very evident, however, 

 that if they are in the nucleolus they do not come out of it as 

 condensed and separate individuals as they do in the other cases 



