534 Theophilus s. Painter, 



be seen hj Figs. 55, 56 and 57. In the latter figure the planosome 

 (marked "P") appears to be made up of two elements. 



Telophase. The accessory chromosome passes to one pole of 

 the cell undivided as it did in the gray variety, but the super- 

 numerary body shows no movement at this time. As the autosomes 

 go apart, we have a small body lagging behind in the spindle (Fig. 58), 

 and this represents the planosome. At this time the planosome 

 appears single and judging from the fact that it lags behind in the 

 spindle, it seems probable that it is distributed, by a matter of 

 chance, to one pole or the other. This point is one that is hard to 

 verify by direct observation. 



Second maturation division. 



In the tufted variety of male we encounter the same difficulties 

 in the study of the second maturation division as we did in the gray 

 variety. The cells are small, the long chromosomes tend to over-lap 



SECOND 



SPERMATOCYTES 



PRIMARY SPERMATOCYTES 



Diagram 11. 



Showing the distribution of the Accessory chromosomes and the Planosomes. 

 X Accessory chromosome. P Planosome. 



and the changes go on with great rapidity. For this reason it has 

 been hard to follow the course of the chromosomes in more than a 

 general way. 



Immediately after the telophase of the foregoing division, the 

 second spermatocytes enter a resting stage (Fig. 59). The accessory 

 chromosome elements divide rather early and pass to the poles of 



