IRWIN I. OSTER 



Table 6. Results following irradiation alone and combined with carbon monoxide pre- or 

 post-treatments of male Drosophila melanosasler germ cells 



„ ,, n- ^ . Pel' cent lethal Per cent 



Cell stage Treatment mutations translocations 



139 . _ 162 



Spermatozoa in females 1600 r 9H4n ^ 



Spermatozoa in females CO+ 1600 r t^j-. = 4-3 



97 

 Spermatozoa in females 1600 r+ CO Tofii'"'^'^ 



Spermatids 1600 r 



Spermatids CO+ 1600 r 



1171 



inhibition of the cytochrome system appears to have no effect during X-ray 

 mutagenesis in Drosophila. On the other hand, akhough it has been found 

 that potassium cyanide, sodium azide, and carbon monoxide are not by 

 themselves mutagenic, some recent results by Clarlc*^ have shown that 

 combinations of either of the first two mentioned compounds with carbon 

 monoxide cause a rise in the lethal mutation rate in Drosophila. It would 

 be of interest to determine the effect of such combination treatments on the 

 formation of chromosomal disarrangements. 



/ wish to thank Professor H. J. Muller for his constant interest during the course 

 of this work. I should also like to express my sincere appreciation to Mrs. Astrid Cicak, 

 who supervised and carried out the work with the help of Mrs. Louise Petoe, Elizabeth 

 Ehrlich, Mae V. Bay, and foyce Stafford. They are to be especially commended for 

 their careful and untiring efforts in executing many of the technical portions of these 

 experiments. 



REFERENCES 



lAuERBACH, C. Z. indukt. Absiamm.- u. VererLehre 86 (1954) 113 



^Khishin, a. F. E. Z. indukt. Abstamm.- u. VererLehre 87 (1955) 97 



^LiJNiNG, K. G. Hereditas, Lund 38 (1952) 91 



"LtJNiNG, K. G. Hereditas. Lund 38 (1952) 321 



sLuNiNG, K. G. Acta zooL, Stockh. 33 (1952) 193 



^LiJNiNG, K. G. Studies on X-ray Induced Mutations in Various Stages of Spermiogenesis in 

 Drosophila melanogaster A. Bonnier's Press, Stockholm, 1952 



"OsTER. I.I. Proceedings of the Fifth International Conference on Radiobiology Stockholm, 

 1956, p. 475 



sQsTER, I. I. Rec. Genet. Soc. Amer. 26 (1957) 387 



sQsTER, I. I. Genen en Phaenen 3 (1958) 53 

 loMuLLER, H.J. Amer. Nat. 64 (1930) 220 

 iiQsTER, I. I. Drosophila Inform. Sen: 29 (1955) 154 

 12CLARK, A. M. Xature, Lond. \11 (1956) 787 

 i^Baker, W. K. and von Halle, E. S. Proc. nat. Acad. Sci., Wash. 39 (1953) 152 



265 



