Studies on Chromosomes 



ii 





H\ 



a 



'/ * c 



Iff * 



FIGURE z 



Anasa tristis. a, Metaphase of first spermatocyte-division, in polar view, showing the nine large 

 bivalents in a ring, the univalent heterotropic chromosome below it, and the m-chromosome bivalent 

 in the center; b, anaphase of second division; c, d, sister-groups from the same spindle, polar view, 

 second division (i the macrochromosome); e, spermatogonial group; /, the same chromosomes arranged 

 in pairs; g, obgonial group from a larva; h, the same group arranged in pairs; /, spermatogonial group; 

 j, group from a dividing follicle-cell; k, double group, from a cell toward the periphery of a larval ovary. 



