12 



MENDELIAN SEGREGATION 



Similarly, a spermatozoon bearing the., factor for 

 vestigial wings fertilizing an egg bearing the factor 

 for long wings produces a hybrid with long wings; a 

 spermatozoon bearing the factor for vestigial wings 



"V" 

 3 



Fig. 6. — Diagram to illustrate how by the random meeting of two kinds 

 of sperm and two kinds of eggs the typical 3 : 1 ratio results. 



fertiUzing an egg bearing the factor for vestigial wings 

 produces a fly pure for vestigial wings. 



Since the sperm and the eggs meet at random there 

 should be 1 pure long, to 2 heterozygous long, to 1 ves- 

 tigial; or putting together all flies with long wings, 

 3 long to 1 vestigial. Three to one is the character- 



