THE GENETICS OF HABROBRACON JUGLANDIS ASHMEAD 



COALESCENT, co (antennae). In a fraternity of 

 v/ild-type stock several males were observed 

 with antennae of approximately normal length 

 but with the segments coalescent. The females 

 are fully fertile with males of normal viability. 

 A few mutations involving leg length and 

 structure and foot structure have occurred in 

 Habrobracon. These factors, like those for eye, 

 v/ing, body, and antennal mutants, may be found 

 singly or in combination. However, leg and foot 

 mutants seem to cause reduced viability. This 

 may be the result of a semilethal or their ina- 

 bility to mate properly. 



BEADED, b (legs). In August, 1929, a fraterni- 

 ty of males was observed containing a number of 

 mutants with beaded legs. The proportions of 

 the various parts of the wing of beaded are 

 very aberrant, and wings often fail to expand. 

 Antennae are very likely to show fusion of seg- 

 ments and often more or less distal deficiency. 

 Beaded is semi-lethal. The mutant types sur- 

 vive much better at 23° C. than at 30° C. Even 

 at higher temperature the majority may attain 

 the pupal stage, but few emerge from the co- 

 coons. Tibiae and femora are much shortened 

 and swollen, the swelling of the tibiae being 

 confined to the distal half (P. W. Whiting, 

 1934b). Males of beaded are fertile, but via- 

 ble females have not been found (P. W. Whiting, 

 1932a). (Discarded) 



STUMPY, st (legs). In September, 1930, a sin- 

 gle male v/ith stumpy legs was found among the 

 offspring of an X-rayed female (dosage about 

 3250 R units). The most striking characteris- 



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