12 



CIRCULAR 349, XJ. S. DEPARTMENT OF AGRICULTURE 



sand around the mangoes at the bottom of the pits. In the dry 

 sand 1 puparium was 6 inches above the fruit; 476 puparia were in 

 the first 4 inches of sand and 1,106 (nearly 70 percent) in the space 

 occupied by the mangoes. 



Table 9. — Numbers of Anastrepha ludens adults and puparia 

 fied depths of sand in pits, 1932 



recovered j 



'rom speci- 





Adults 



Puparia • 





Wet 

 sand 



Dry sand 



Wet 

 sand 



Dry sand 



Depth (inches) 



Pit 

 1 



Pit 

 2 



Pit 

 4 



Pit 

 6 



Pit 

 8 



Pit no. 

 1 



Pit no. 

 2 



Pit no. 

 4 



Pit no. 

 6 



Pit no. 



8 





"3 



o 



1? 



ft 



a 



"3 

 o 

 Eh 



>> 

 ft 



a 



o 



Eh 



ft 



a 



w 



3 

 o 



Eh 



ft 



a 



H 



1 

 6 

 50 



240 



o 



E- 



2 



1 

 71 



221 



>> 



ft 



g 



1 _. 



2 



} « 



1 



1 



3 



2 



7 



21 



25 



42 



44 



15 



( 2 ) 



( 2 ) 



1 

 7 



12 

 28 

 38 

 46 



33 



( 2 ) 



( 3 ) 



4 

 11 

 14 



2 26 

 22 



2 32 

 44 



42 



2 



26 

 12 

 29 



6 



4 

 7 

 19 



157 



2 



7 

 15 



139 



1 



5 

 11 

 74 

 176 



319 



5 



8 

 47 

 146 



260 



1 



2 



12 

 45 



262 



1 



8 

 38 



214 



3 



6 



67 



304 





2 



3 





4 





5. 





6 



7 





8- 





9. 





10 





11 





12 





13 





14 





15_ 





16. 



2 



17 



1 



18 



60 



19 4 





20< 



197 







Total 



6 



161 



165 



195 



75 



187 



163 



586 



466 



322 



261 



380 



297 



295 



?60 







1 Total puparia include empty puparia and those from which no adults emerged; empty puparia include 

 also caudal ends or mid-sections, the larger number being taken. 

 2 1 dead larva. 



3 2 dead larvae. 



4 This 2-inch layer was occupied by mangoes. 



DISCUSSION 



The experiment clearly shows that 18 inches of well-packed sand, 

 either wet or dry, placed above the fruit is sufficient to prevent the 

 emergence of Anastrepha ludens adults. Moistened sand, when 

 packed, becomes hard and caked and for this reason appears more 

 satisfactory than packed, dry sand. It is probable that fruit would 

 not have to be buried so deep if moist sand were used, but more data 

 will be needed before a shallower depth can be recommended. 



It should be noted that all these experiments were carried on with 

 mangoes, primarily because they were available at a time in the dry 

 season most suitable for carrying on field experiments. It would 

 have been much better if weU- infested citrus fruit had been available. 

 While no comparative data are available, it is believed that these 

 results will hold for citrus as well as mangoes. 



In the summer of 1931 the writers had the opportunity to observe 

 what takes place when large numbers of mangoes are piled together 

 and covered with 6 to 8 inches of soil. Many of these mounds were 

 broken up late in the season in a search for living larvae and puparia 



