220 ' A^. M. Stevens 



Description of Figures 



Fig. 17 Later prophase. Ac-c. 



Fig. 18 Still later prophase from a section; showing the shorter pair (a), a figure 8 (b) which later 

 appears as a ring, and a second long pair (c). 



Fig. 19 Section of a prophase showing the plasmosome (p) still present. 



Figs. 20 and 21 Exceptional prophases in which one pair, apparently the shorter one, was completely 

 condensed earlier than the other two pairs. Ac-c. 



Fig. 22 Typical first spermatocyte metaphase. Ac-c. 



Fig. 23 Chromosome bivalents from the same cell drawn separately. Ac-c. 



Fig. 24 Chromosomes from a slightly earlier stage, a spindle prophase. Ac-c. 



Fig. 25 a and b The ring chromosome. Ac-c. 



Fig. 26 Three chromosome pairs from one spindle showing the ring-chromosome forming a cross 

 ■where the ends are united. Ac-c. 



Figs. 27, 28, 29 Other groups of chromosomes, each group from one spindle. Ac-c. 



Fig. 30 Pair of chromosomes showing extreme case of overlapping, from a metaphase. Ac-c. 



Fig. 31 Another metaphase group. Ac-c. 



