690 



THE RESPIRATION AND 



[PT. Ill 



carbon dioxide excreted per gram egg per hour — therefore not 

 metaboHc rate) . In Crioceris asparagi, Hylemyia chortophila, and Leptino- 

 tarsa decemlineata (the asparagus beetle, the seed-corn maggot, and 

 the potato beetle respectively) the formative period is evidently very 

 brief, not occupying more than a single day, but in Popillia japonica 

 (the Japanese beetle) it lasts for more than 6 days, and, when the 

 respiration does rise, it rises very steeply. The formative period 

 mentioned by Fink perhaps corresponds to the early flat part of the 

 curve in the case of the measurements on the silkworm egg by 

 Luciani and Farkas, but, as in nearly all cases (e.g. the chick) 



'zzz-±-_zp 



fl 3 /- 



S, JL 



|. _^L 



6 

 5 



s 



£ 

 O 



123456 789 10 11 

 Days 



Popillia japonica 



1 234 5 6 789 10 11 12 



Days 



Cotinis nitida 



Fig. 138. [The upper solid line in each figure represents the Oj intake, the lower solid line the COo 

 output, and the dotted line the R.Qj) 



respiration rises in a curve convex to the abscissa, it is questionable 

 what definite meaning can be attached to the "formative period". 

 Fink suggested that there was a correlation between short formative 

 period and the deposition of eggs on foliage or soil surface (examples 

 would be Leptinotarsa and Hylemyia) on the one hand, and between 

 long formative period and deposition of eggs at some depth below 

 the surface of the soil (examples : Popillia and Cotinis nitida (the green 

 June beetle)). 



Fink drew a very interesting comparison between embryonic re- 

 spiration and the respiration in metamorphosis when he set side 

 by side the carbon dioxide and oxygen turnover per gram per hour 

 during the two processes. 



