GENE MUTATIONS 



CONSTRICTED, Cs (fe:Tiora). In August, r-)30, a 

 single female was observed v/ith constricted 

 femora. This mutant type is dominant and ap- 

 parently lethal in the male. It is difficult 

 to obtain offspring from constricted females, 

 and fraternities are small. The difficulty is 

 probably mechanical and concerned with feeding 

 from the caterpillars. The trait appears in 

 all three pairs of legs but is most obvious in 

 the metathoracic pair (P. W. Whiting, 1932a). 

 (Discarded) 



CLUB, cl (tarsi and wings). In July, 1931, a 

 mated wild-type female X-rayed (dosage about 

 3270 R units) produced among her offspring 

 eight males with club feet. The terminal seg- 

 ments of the tarsi are much malformed, fused, 

 and sv/ollen. The v;ings show more or less ab- 

 normality with a tendency to form extra veins 

 in the radial cell. Club males are about fifty 

 per cent as frequent as their normal sibs. Fe- 

 males fail to oviposit even v/hen caterpillars 

 have been stung by another wasp. A recurrence 

 of club appeared in the offspring of an X-rayed 

 female (dosage about 3500 R units) in the sum- 

 mer of 1934 (P. W. Whiting, 1935b). The hind 

 feet of the club males are flattened and curved 

 down. The antennae droop terminally with de- 

 formation of three or four segments. There is 

 a high percentage of pupal inviability, but the 

 males proved fertile. (Discarded) 



FOOTLESS, fo (feet). In March, 1933, fifty-two 

 males appeared in the offspring of a heterozy- 

 gous virgin female which were footless. This 

 mutant type is characterized through a defect 



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