256 



Journal of Agricultural Research 



Vol. VI, l^To. 7 



Table IV. — Effect upon Mediterranean fruit-fly pupce of refrigeration for from j to 14 



days at 38° to 40° F. 



Age of pupae on entering storage. 



Number of pupse yielding adults on removal to normal tem- 

 perature after refrigeration for — 



3 days. 4 days 



6 days. 7 days 



8 days. 



days. 



days. 



days. 



1 day. 



2 days 



3 days 



4 days 



5 days 



6 days 



7 days 



8 days 



no 



150 

 62 



35 



91 



132 



235 

 207 



13 

 170 



58 

 41 

 86 

 82 

 117 

 234 



S 

 75 

 81 

 16 

 52 

 59 

 114 

 136 



I 



119 



23 



13 



63 



52 



121 



161 



5 

 121 



4 

 19 

 24 



23 



96 



180 



I 



145 

 6 



4 



9 



6 



60 



61 



124 



4 



I 



12 



7 

 32 

 63 



I 

 42 



4 

 I 

 6 

 o 

 22 

 19 



After refrigeration for 17 days only 3 out of 306 eight-day-old pupae, 

 3 out of 384 seven-day-old pupse, 3 out of 206 six-day-old pupae, i out of 

 162 four-day-old pupae, and 11 out of 374 two-day-old pupae yielded 

 adults, or only 21 out of 2,352 pupae of all ages survived. 



After refrigeration for 18 days only 9 out of 701 eight-day-old pupae, 

 5 out of 250 seven-day-old pupae, i out of 295 five-day-old pupae, i out of 

 430 three-day-old pupae, and 13 out of 400 two-day-old pupae yielded 

 adults; or only 29 out of 2,632 pupae of all ages survived. 



Nineteen days of refrigeration proved fatal to 1,911 pupae of all ages 

 except 2 out of 375 one-day-old pupae. No living pupae were found 

 among 2,031 pupae of all ages after refrigeration for 21 days, nor among 

 28,700 pupae of all ages after refrigeration for 35 days. 



Temperatures op from 40° to 45° F. — In this experiment to deter- 

 mine the effect upon pupae of temperatures ranging between 40° and 

 45° F., 8,800 pupae from i to 10 days old were used. Each unit of 

 pupse contained 100 forms; hence, the numbers of pupae yielding adults 

 after refrigeration from i to 27 days as recorded in Table V represent 

 the percentages of survival. 



Table V. — Effect upon Mediterranean fruit-fly pupce of refrigeration at 40° to 45° F .for 



from I to 2/ days 



Age of pupae on 

 entering storage. 



1 day. . 



2 days. 



3 days. 



5 days. 



6 days. 



7 days. 



8 days. 



9 days. 

 10 days. 



Number of pupse yielding adults after removal to normal temperature after — 



I day. 3 days. 6 days. 8 days. 10 days. 12 days. 16 days. 18 days. 24 days. 27 days 



81 

 69 



47 

 66 



91 



55 



78 

 77 

 91 

 63 

 82 



87 

 60 



« 17 « 23 



15 



59 



I 



38 



72 



75 

 44 



^21 



13 

 58 



54 



24 



49 

 60 



27 



13 



13 

 31 

 57 

 16 



«! 



18, 28, 30, and 10 pupae, respectively, yielded adults just before pupae were placed in 



" Besides these, 

 cold storage. 



