GENE MUTATIONS 



regular wrinkling of the wings results, and 

 portions of the integument are found adhering 

 to the antennae which show a tendency to frag- 

 ment. Wrinkled is fertile in both sexes but 

 is mechanically hampered in eclosion and in 

 other activities. (Discarded). 



REDUCED, r (wing size). This mutation occurred 

 in March, 1925 (P. W. Whiting, 1926b) in a sin- 

 gle male which had small wings and irregular 

 reduced venation (Fig. 7). The trait is varia- 

 ble but always distinct from type. Reduced af- 

 fects chiefly the middle area of the wings and 

 usually causes disappearance of vein m-cu. It 

 is of good viability and fertility in both 

 sexes. 



SHORT, sh (wings). This mutation was first ob- 

 served in cultures derived from some of the 

 sibs of the miniature mutants (P. W. Whiting, 

 1932a). It is uncertain whether short occurred 

 as a mutation at approximately the time of the 

 mutation to miniature or whether it had been 

 carried in the stock. Short is very suscepti- 

 ble to temperature, overlapping with normal to 

 a considerable extent. It is impossible to 

 distinguish a culture of short from type when 

 reared at room temperature. Under standard 

 conditions, 30° C, wings of short average much 

 smaller, but even in this case there is more or 

 less overlapping. Females are fully fertile, 

 and males are of normal viability. (Discarded) 



NARROW, n (wings). Narrow v/as first observed 

 in April, 1930. Fourteen males appeared from a 

 cross between a type female and a type male 



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