20 



Linkage Group I. 



glazed in structure, but it is more like wax in shape, and has a bushy appearance, 

 due to heavy black hairs or clusters of hairs on the surface. Lozenge females appear 

 to be partly sterile, but do not show such a high degree of sterility as do those of 

 glazed and wax. An allelomorph of lozenge — lozenge-2 — bears a close resemblance 

 to wax in appearance, and probably had sterile females, according to information 



Fig. 5.— Cut. 

 Droop (d). (Figure G.) 



furnished us by Dr. Sturtevant and Dr. 

 Bridges. The stock of lozenge-2 has been 

 lost, however, and we have not been able 

 to compare specimens with those of wax. 

 Description. — The wings of droop flies 

 curve downward or droop at the ends. 

 The character usually appears in both 

 wings, but sometimes appears only in one 

 or fails to appear at all. 



Fig. 6. — Droop. (Legs are normal, 

 not short, as indicated.) 



Origin. — (E 780.) 14 droop males were obtained from a pair mating of scaly 

 flies, indicating that the mother was heterozygous for droop. 



Comparison. — In appearance droop resembles the sex-linked character "depressed" 

 in D. melanogaster (Morgan and Bridges, 1916, p. 67), but differs from the latter in 

 being inconstant. 



