ISPIRATORY METABOLISM. 13 



Table V. gives examples of the variations in carbon dioxide 

 production in ten different lots of ten wild and ten vestigial pupje. 

 A rather wide range of variation will be noted in the time taken 

 by different lots of the same age to produce the same amount of 

 carbon dioxide. 



These studies are being continued in this laboratory, with the 

 idea of investigating, in a quantitative manner, the possible effects 

 of different factors upon the physiological make-up of the organ- 

 ism, as well as differences due to sex and species. 



SUMMARY AND CONCLUSION. 



1. Xo -i-nificant differences in air consumption (O, and CCX) 

 in culture little- with different types of stoppers, all other con- 

 ditions p-maining the same, have been found. 



2. Thei u'radual decrease in body weight during pupal 



mcnt of the fly. 



3. Kates of oxygen consumption and carbon dioxide output 

 of pupre follow ilHmitelv shaped curves. 



|. Tlu- <lrrease in oxygen consumption and carbon di- 



!< output tin- strond day of pupal life followed by a gradual 

 incp-asr up to the time of hatching. 



;. A c.i::!par>on of the rates of respiratory metabolism of two 

 tvprs of tlii--. wil-l and vestigial, has been made and more exten- 

 sive expiTimt 'in necessary before differences found in these 

 stocks can 1><- <li -finitely established. 



LITERATURE CITED. 

 I. Morgan, T. H. 



'19 1 -is of Heredity. Pli ia. 



J Loeb, J., and Northrop, J. H. 



'16 Proc. N.I: \rad. Sci., Vol. 2, p. 456. 



17 Id. Ibid.. Vol. j. P- 386. 



'17 Id. Imir hem.. Vol. 32, p. 103. 



Northrop, J. H. 



'17 Ibid.. \ .-I. 23. 



3 Pearl, R., and Parker, S. L. 



'21 The American ist, Vol. 55, p. 4> v i. 



*22 Id. Ibid.. \ . p. 174. 



'22 Id. Ibid., Vul. 56. p. 273. 

 '22 Id. Ibid , Vol. 56, p. 312. 

 '22 Id. Ibid . Vol. 56, p. 385- 



