FORMATION OF THE FIRST SPERMATOCYTE CHROMOSOMES 563 



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Fig. 2 Specimen 29-2. A, B, C, serial sections, side view, of a single meta- 

 phase plate, first division with 14 chromosomes, showing that four of these are 

 univalent and 10 bivalent; D, E, F, G, serial sections of a metaphase plate with 

 13 chromosomes showing 11 biavalent and two univalent ones; H, I, J, K, same as 

 D, E, F, G; L, M, N, 0, serial sections of a metaphase plate with 12 chromosomes 

 showing that all of them are bivalent; P, Q, R, S, anaphases of the first maturation 

 division showing the behavior of the single chromosomes. 



