DISPOSAL BY BURIAL OF FRUIT-FLY INFESTED FRUIT 13 



It was noted that many full-grown larvae had been killed. It is 

 thought that this was the result of fermentation processes that took 

 place in the fruit. No similar observations were made in the depth- 

 of-bunal studies, in which very few dead larvae were found. 



PACKING EXPERIMENT 



In the experiment of 1931 it was noted that the soil sank approxi- 

 mately 1 inch when packed, irrespective of the depth of the pit. The 



S 1 J' E ?? ct °. Packing (with 15- or with 25-pound implements) on successive 1-inch layers of screened 

 rL n £? n A S01 J m Plts - i? each . d i ag 1 ra , m tbe P° sition s of the 1-inch layers in the pit before packing are rep- 

 resented by transverse lines at the left; these are connected with transverse lines at the right repreSnS 



wi P d epreSed. **"* ^ Pa ° g ' With figUreS showin§ the distance (in taSSjttJRSSBSS 



experiment of 1932 clearly indicated that packed moist sand was 

 superior to packed dry sand as a covering for infested fruits buried in 

 pits. 



Packing appeared to be such an important factor in preventing 

 fruit fly adults from emerging from the burial pits that experiments 

 were carried on m Mexico City in 1933 to learn more about the effects 



