THE CHROMOSOMES 



117 



and on the other side hybrid in character and 

 probably came from such half-fertihzed eggs. It 

 will be recalled that Baltzer has shown that when 

 the cross is made in this direction both paternal and 



^;0 oy 



.nimll:. f?;rl' ^"^ chromosomes of the egg he in the equator of the 



W ' W./tL'^'?'''''Ti!' ""^ *^^ 'P^^"' ^* °^^ «^^^' 2, a later stage show- 

 f^,\f the paternal chromosomes lymg at one side passing to one pole' 

 3 (to the right), later stage; the conditions are the same; there is afso a 

 supernumerary sperm m the egg (shown to the left, in another sect on )^ 



^T'^aTu^T ^'>'*' ?' P^^*^^^ 1^^^^ that is purely maternal on one 

 side, and hybrid on the other. (After Herbst.) 



maternal chromosomes behave normally at each 

 division. The conclusion follows with much plausi- 

 bility that the absence of paternal characters on one 

 side IS due to the absence of paternal chromosomes 

 on that side. 



