276 



SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 1 37 



AGE IN DAYS 



Fig. 9. — Cytochrome c oxidase activity of Drosopkila virilis during the pupal 

 period and the first 4 days of adult life. Abscissa : A, pupil period ; B, adult 

 period ; O, puparium formation ; Oi, emergence of fly. Ordinate : cytochrome 

 c oxidase activity. Numbers above indicate numbers of pairs used for the de- 

 termination of each age group. (After Bodenstein and Sacktor, 1952.) 



CYTOCHROME AhTD INSECT FLIGHT 



Fig. 10.- 



6 7 



AGE IN DAYS 



-The dry weight of Phormia sarcosomes as a function of fly age. 

 (After Levenbook and Williams, 1956.) 



