THE GENETICS OF HABROBRACON JUGLANDIS ASHMEAD 



tv/een speckled and reduced, and about 15 per 

 cent crossing over betv/een reduced and glass. 

 The sex gene lies to the right of glass and is 

 followed by fused and stubby, which have been 

 shown to be sex-linked. The strength of the 

 sex linkage of fused has been shown to vary 

 from 8,6 per cent to 17,6 per cent crossing 

 over (P. W. Whiting, 1940e). Kager (1941) work- 

 ing v/ith orange-eyed females heterozygous for 

 stubby, showed crossing over to be 37.5 per 

 cent between stubby and the sex gene, and 24.2 

 per cent betv/een stubby and fused. Linkage 

 across the sex gene indicates that speckled 

 and stubby appear to segregate independently, 

 and no linkage between speckled and fused is 

 noted. Stubby shows very slight, if any, link- 

 age with reduced or with glass. A study by 

 P. W. V/hiting and Benkert (1934) indicates link- 

 age between reduced and fused with 45.5 per 

 cent crossovers. Linkage between fused and 

 glass, with 41.7 per cent recombinations, sug- 

 gests that glass is nearer fused than is re- 

 duced. Recent experiments bear out this con- 

 clusion. No conclusive evidence is as yet 

 available for the sex linkage of glass, which 

 may be very loose or may be masked by a third 

 allele and by viability differences. A linkage 

 map of regions near the sex gene with approxi- 

 mate intervals may be constructed as follows: 



Sk —13-- r ~-15'- g l x >-10«- fu —24— sb 



Anderson and P. W. Whiting (1939) reported a 

 "cantaloup" group of 14 loci with a map dis- 



106 



