A STUDY OF OXYGEN METABOLISM IN 

 DROSOPHILA MELANOGASTER. 



M. R. CLARE. 



INTRODUCTION. 



Although Drosophila melanogaster is uniquely favorable as 

 material for genetical studies, relatively few physiological in- 

 vestigations have been conducted upon this animal. Its small 

 size has certainly been a deterrent to such studies; yet, with 

 suitable apparatus, this feature is unimportant. To supplement 

 the remarkably full record we possess for its genetical behavior 

 physiological studies are especially desirable, and an attempt is 

 made in this paper to show the practicability of investigations 

 into the metabolism of this fly and also to illustrate the type of 

 results which such study can be expected to yield. The in- 

 vestigation was undertaken primarily to determine to what 

 extent degree of inbreeding may be reflected in metabolism. 



Measurements were made of the oxygen consumption of 

 Drosophila pupae, and these proved admirably adapted to this 

 purpose. At no time during pupal life except at its extreme 

 termination are results complicated by muscular movements, 

 hence standard metabolism alone is measured. Moreover, the 

 fly is so amenable to conditions of laboratory culture that 

 experimental pupae are available at all times and can be grown 

 under standard conditions. 



The investigation was conducted at the University of Penn- 

 sylvania, for which privilege the writer desires to acknowledge 

 his indebtedness to Doctor C. E. McClung. He is under special 

 obligations to Doctor J. H. Bodine, who not only suggested the 

 problem but was ever ready with helpful suggestions throughout 

 the progress of the work. The stocks of experimental flies were 

 kindly contributed by Doctors C. B. Bridges, H. J. Muller, 

 L. E. Griffin, Chas. Zeleny, J. H. Bodine and R. L. King. 



MATERIAL AND METHODS. 



Eight stocks of "wild" Drosophila melanogaster -were employed 



in the study. Three of these were caught shortly before the 



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