SHORTER ARTICLES AND DISCUSSION 



In September, 1913, a new eye-color "scarlet," appeared in 

 one of my cultures of Drosophila repleta Wollaston. The new 

 eye color is a bright scarlet when first hatched and darkens but 

 little with age. The eyes of the wild flies, on the other hand, are 

 a deep mahogany which darken soon after hatching until they are 

 almost black. This last statement is true of the stocks I have 

 found in New York City, Woods Hole, Mass., North Manchester, 

 Ind., Brazil, Ind., and Terre Haute, Indiana. The eye-color of 

 the newly emerged mutant corresponds to the color chart in 

 Ridgeway 's Color Guide, Plate VII, No. 11 (Boston, 1886) . The 

 large scarlet eye in contrast to the dark body of the fly makes 

 the new repleta an object of great beauty as contrasted with the 

 wild species. 



The new fly in all probability came from heterozygous stock, as 

 is shown by the following facts. The original stock was obtained 

 by exposing a fruit jar with banana in a fruit store in North 

 Manchester, Indiana, September 10, 1913. From this bottle 1 

 there hatched 777 $$ and 206 of Drosophila ampelophila. 

 On November 5 appeared repletas. November 15, I found one 

 scarlet female among 35 repletas. November 16, one scarlet 

 male among 20 flies. November 17, one scarlet female among 

 25 flies. Some of the virgin flies were isolated and four scarlets 

 appeared on January 24. My assistant, Mr. Powell, also isolated 

 some of the original stock and later found three scarlets. This 

 would seem to show that the stock had mutated some time before 

 being taken into captivity. During September, 1915, I set a 

 great many traps in the region where the above stock was taken, 



1 1 should call attention to the aberrant sex ratio found here in Droso- 

 phila ampelophila. Culture from this stock later gave 491 and 45 

 I have data on the sex-ratio in this species for over three years and in 

 many different stocks. With this exception I have found it approaching 

 equality. I mated 25 pairs of virgin flies from this stock with the expecta- 

 tion of finding a sex-linked lethal but in each of the twenty-five bottles the 

 sex-ratio was practically one of equality. The subsequent history of the 

 stock was not followed, owing to an accident. 



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