EXPLANATION OF PLATES 



The complexes were drawn with the aid of a camera lucida at a magnification 

 of 2400 diameters. In the reproductions they appear at 1600 diameters. The 

 chromosomes were rearranged for the plates roughly according to size by tracing 

 from the original drawings. 



The haploid complexes are from side views; the diploid complexes from polar 

 views. Each horizontal row represents the chromosomes of one cell, each ver- 

 tical row corresponding chromosomes from different cells. The arrangement is 

 such that the accessory, no. 6, is always passing to the upper pole. 



Column 3 is left vacant since the member which belongs here is united with 

 one of the others to form an octad. 



PLATE 1 



EXPLANATION OF FIGURES 



1 to 4 Complexes involved in mating no. 2. 



1 First spermatocyte complex of father; pair no. 6 atelomitic, pair no. 1 hetero- 

 morphic. 



2 Spermatogonial complex of father. 



3 Somatic complex of mother; pair no. 6 heteromorphic, pair no. 1 telomitic. 



4 First spermatocyte complex of a son; pair no. 6 heteromorphic, pair no. 1 

 telomitic. 



5 to 7 Complexes involved in mating no. 13. 



5 First spermatocyte complex of father; pair no. 1 atelomitic. 



6 Somatic complex of mother; pair no. 1 telomitic. 



7 First spermatocyte complex of a son; pair no. 1 heteromorphic. 



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