106 



THE THEORY OF THE GENE 



fclH ill 



'^v 



• • 



d 



•• • 

 *• • 



Fig. 62. 

 Chromosomes of Metapodius. a, spermatogonia! group with three 

 small m-chromosomes; & and c, side view of spermatocytes, con- 

 jugation of three m's, two pass to one pole, one to the other, as 

 seen in d and e (anaphase plates of c). (After Wilson.) 



species where the female has one chromosome more 

 than the male, and there are other species where the 



in the eggs and sperms, are separate in the embryonic cells. In the bee each 

 chromosome is supposed to break into two parts in all of the somatic cells. 

 In some of the tissue cells of flies and other animals the chromosomes may 

 divide without the cell dividing and in this way become doubled or quad- 

 rupled. 



