17-1 The Effect of Various Chemicals on Blow- Fly 



TABLE III {continued). 



The results obtained in this series of experiments are extremely 

 erratic ; this might conceivably be chiefly due to two causes. 



(a) Death might be due to starvation; the high mortality in 

 the controls pointed to this; 



(6) Larvae of mixed ages were employed, and these might have 

 very different powers of resistance towards the toxic agent. 



The next series of experiments was devised to test these two points. 

 The young and old larvae were kept apart and experiments carried out 

 on each. As before, a definite number were shaken with the powder 

 and then placed in a glass jar in sand, meat being added in each case 

 to prevent death by starvation. 



The results are shown in Table IV. 



