26 Linkage Group I. 



Rugose, Glazed, and Wax. 



Since rugose is the best of these three allelomorphs for use in linkage experiments, 

 the present data are nearly all based on this character. These are summarized under 

 experiments 9, 14, 16, 18, 33, 35, 38, 39, 43, 44, and 47. The locus of rugose is 

 placed on the map on the basis of the short-rugose value of 15.9, which gives rugose 

 a position at 102, based on 1,564 flies. This is about 4 units beyond the position 

 given by using the forked-rugose value, but is believed to be more accurate than the 

 latter, since it eliminates most of the undetected double cross-overs. 



Droop. 



Droop has been used in experiments with singed, magenta, forked, triangle, short, 

 and rugose (table 3). These agree in indicating that its locus is in the lower part of 

 the map, and experiments 32 and 33 show that it falls beyond rugose, which has 

 previously marked the extreme end of the map. Its position is determined with 

 reference to rugose by experiments 18 and 33, which place it 7.2 units from rugose, 

 or at approximately 109. 



