126 THEORY OF EVOLUTION 



In man the sex formula appears to be XX 

 for the female and Xf) for the male ( fig. 60 ) , 

 and since the relation is essentially the same as 

 tliat in Drosojjhila the chromosome explanation 



^.:'r>- tit'iermi /ifriion ui ///an ()17/iimitfer.) 





A 



v. 



•ttfdtw^ 







/V;f 



V*-*"*-^- 





Fig. 61. Spermatogenesis in man. There are 47 chromo- 

 somes (diploid) in the male. After reduction half of the 

 sperm carry Si cliromosomes (one of which is X) and lialf 

 carry 33 chromosomes (no X). 



is the same. According to von Winiwarter 

 tliere are 48 cliromosomes in the female and 47 

 in the male (fig. 61). After the extrusion of 

 the polar bodies there are 24 cliromosomes in the 

 egg. In the male at one of the two maturation 



