JOSEPH KRAFKA, JR. 



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TABLE X. 



Qio (Calculated from Qti-t^ for Facet Number in Ultra-Bar Females. 



TABLE XI. 



Qio (Calculated from Qti-h) for Facet Number in Low Selected Females. 



Temperature Effect on the Rate of Development. 



The time-temperature curves, representing the number of days 

 necessary to pass through a given stage in the life history, give an 

 interesting set of data with which to compare the facet curves. Table 

 XII gives the number of days at the respective temperatures necessary 

 to complete the egg, larval, and pupal stages. Loeb has treated in 

 full the subject of the length of the various metamorphic phases in 

 Drosophila as affected by temperature. As my results are consistent 

 with his in as far as the type of curve is concerned, I shall say nothing 



