GENE MUTATIONS 



narrower with more or less fusion and deletion 

 in both sexes. 



DWINDLING, dw (antennae). In July, 1931, a mated 

 wild-type female was X-rayed (dosage about 3200 

 R units). Among her offspring was one male 

 with dwindling antennae. This mutant type shows 

 much irregularity and fusion of antennal seg- 

 ments in the male, but the proximal half of the 

 antenna is not affected. Females of dwindling 

 cannot be distinguished from wild-type pheno- 

 typically. Dwindling males are numerically 

 equal to somewhat over two-thirds of their nor- 

 mal brothers. (Discarded) 



ATTENUATED, at (antennae and genitalia). In 

 May, 1932, a fraternity was bred consisting of 

 males, fifty per cent of which had antennae 

 with much malformation and fusion terminally. 

 Genitalia were also abnormal, and the type 

 could, therefore, not be perpetuated. The mu- 

 tation has been reported, and the mutant type 

 figured (P. W. Whiting, and A. R. Whiting, 1934) . 

 The antennae are similar'in appearance to those 

 of dwindling. (Discarded) 



GYNOID, gy (antennae and abdominal sclerites). 

 In April, 1932, among the offspring of a het- 

 erozygous female, a male appeared having short 

 antennae resembling those of a female. This 

 mutant type, gynoid, the gene for which causes 

 haploid males to be weakly intersexual was 

 later described by P. W. Whiting, Greb, and 

 Speicher (1934). Gynoid males are similar to 

 normal males in internal structure and in ex- 

 ternal genitalia. Their ocelli are large re- 



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