of oxygen consumption at the beginning of the eonymphal stage we can 

 observe also an intensive decrease in cytochrome oxidase and succinic de- 

 hydrogenase activity (Fig. 2). At the second part of sawfly metamorphosis with 

 an increasing oxygen consumption a corresponding rise of succinic dehydro- 

 genase and cytochrome oxidase activity could be registered (Tab. 1). The lowest 

 activity of these enzymes was ascertained just during diapause and in the 



-nm^ Oy/grarryhour 

 900- 



800 



400- 



300- 



200- 



100 



>iu5ing eonymphs 



ausing pronymphs 



10 15 20 25 30 temperature '^ С 



Fig. 3. The effect of temperature vipon oxygen consumption of several developmental 



stages in Cejjhalcia abietis. 



period of low metabolic rate. In the sawfly Cephalcia abietis L. where the period 

 of histogenesis and histolysis of mesonymph are separated from other stages 

 by diapause a slight respiration rise and a corresponding increase of succinic 

 dehydrogenase activity have been found during this period. 



Experiments concerning the influence of temperature on respiratory meta- 

 bohsm revealed the lower is respiratory metabolism and respiratory enzymes 

 activity the smaller temperature effect on the respiration may be seen. This 

 observation confirms investigations made on other insect species (see Kuznet- 

 zoff 1953). Respiratory metabolism of diapausing eonymphs and pronymphs 



198 



