PLATES 3 AND 4 



EXPLANATION OF PIGtJRES 



15 to 28 Complexes involved in mating no. 14. 



15 First spermatocyte of father; tetrad no. 7 is a heteromorphic atelomitic. 



16 Somatic complex of mother; pairs no. 7 and no. 8 heteromorphic. 



17 to 28 First spermatocyte complexes of twelve sons; tetrads no. 7 and no. 

 8 show the various combinations in different individuals to be expected from a 

 free union of the gametes of the parents. 



478 



