No. 585] SHORTER ARTICLES AND DISCUSSION 



577 



be placed upon any variant from the expected classes due to 

 contamination ; for the variant, if arising from the cross, would 

 give some offspring in the F., generation with some of the reces- 

 sive characters. However, extreme care was taken to avoid con- 

 tamination and at no time was there reason to suspect it in any 

 of the cultures. 



The wild stocks used were from Arkansas. California, Massa- 

 chusetts, Illinois. Minnesota. Ohio. Wyoming, Porto Rico, Cuba, 

 Australia and France. The totals of the F generations are as 



follows: 



Total 6,946 5,298 4,393 



This gives a grand total of 16,637 flies. It should be noted 

 that these Mies were examined with the greatest eare under a 

 binocular microscope. Each fly was turned over separately and 

 every part carefully examined. 



From the cherry club vermilion crosses the following ab- 

 normal forms were found; three gynandromorphs ; twenty-four 

 flies with more or less beaded wings; two flies with three cross 

 veins on the wings; one truncate; and two flies with abnormal 

 abdomen. 



The abnormal forms from the crosses with black purple ves- 

 tigial arc speck were, sixty-three with more or less beaded wings; 

 one truncate ; one abnormal abdomen ; one fly with five legs ; and 

 four flies with a projection from the posterior cross vein toward 

 the base of the wing. 



From the black pink bent crosses were found two beaded; one 

 abnormal abdomen ; three truncate ; and one called furrowed be- 

 cause of the furrows in the eyes due to the foreshortening of 

 the head. 



This gives a total of 109 abnormal forms or one abnormal in 



