110 



BULLETIN 536, U. S. DEPARTMENT OF AGRICULTURE. 



In a second room, the temperature of which ranged from 26° to 30° F., infested 

 peaches were placed. An examination of the contained larvae after refrigeration gave 

 results similar to those above; 21, 9, 9, and 19 larvae were found dead after 5, 6, 9, and 

 12 days of refrigeration, and 336 removed after refrigeration from 13 to 15 days were 



Second-instar larvae,. — A total of 3,216 second -instar larvae were subjected to freezing 

 temperatures with the following results: 367 of 377, 77 of 123, and 9 of 195 larvae were 

 found living on removal to normal temperatures after refrigeration for 1,2, and 3 days, 

 respectively, at 21° to 29° F. An average of 361 larvae removed after refrigeration 

 4, 5, 6, 7, 8, 9, and 10 days were dead. No living larvae were found after the third day 

 of refrigeration. 



Third-instar larvse. — Of a total of 6,774 third -instar larvae in kamani nuts (Termi- 

 nalia catappa) subjected to freezing temperatures ranging between 22° and 27° F. for 

 1 to 9 days, 82 of 157 and 4 of 510 larvae were found alive upon removal after refrigera- 

 tion at 24° to 27° F. for 1 and 3 days, respectively. Only 3 of 524 were alive on 

 removal after 4 days of refrigeration at 22° to 27° F. An average of 1,221 larvae 

 removed daily between the fifth and ninth days of refrigeration were dead. 



After refrigeration at 26° to 30° F. 114, 7, 1, 12, and 124 larvae in peaches were 

 foimd dead on removal after 5, 6, 9, 12, and 15 days, respectively, of refrigeration. 

 Ten badly infested peaches were removed to the laboratory after 3 days of refrigera- 

 tion and from two of these there later emerged 1 and 9 full-grown larvae which pupated 

 normally and produced adults. No adults were reared from 15 peaches removed 

 after 14 days of refrigeration. 



Fourteen peaches held in refrigeration 5 days at 26° to 30° F., then successively for 

 24 hours each at 33° to 38° F. and 40° to 45° F., were removed to the laboratory. A 

 total of 36 third-instar larvae, found within the fruit, were dead. 



THE PUPA. 



A total of 21,450 pupae have been subjected to freezing temperatures varying from 

 24° to 32° F. and averaging about 26° F. All pupae were fatally injured before the 

 end of the fourth day of such refrigeration. Three himdred 3-day-old pupae, 100 

 2-day-old pupae, and 200 1-day-old pupae on removal to normal temperature after 

 3| days of refrigeration at about 26° F. produced 1, 1, and 1 adults, respectively. 

 Under similar conditions only 2 of 100 4-day-old pupae and 3 of 200 3-day-old pupae 

 produced adults after 3 days of refrigeration. Each lot of pupae ranging from 1 to 9 

 days old and totaling 1,900 individuals yielded from 2 to 22, or a total of 78 adults, 

 after 2 days of refrigeration. Even 1 day of refrigeration at 26° F. proved fatal to a 

 large percentage of pupae, especially the younger, as evidenced by data in Table 

 XXX covering observations on 1,500 pupae. 



Table XXX. — Effect of 26° F. upon pupal life. Pupse placed in cold storage Oct. 27, 

 1914; removed to normal temperature Oct. 28. 



Age of 



Number 

 of pupae. 



Number of adults emerging on— 



(days). 



Oct. 30. 



Oct. 31. 



Nov. 1. 



Nov. 2. 



Nov. 3. 



Nov. 4. 



Nov. 5. 



Nov. 6. 



Nov. 7. 



Nov. 8. 



9 



100 

 100 

 100 

 200 

 200 

 200 

 200 

 200 

 200 



5 



1 



18 

 6 



4 



42 



5 

















8 



10 

 15 















7 



12 



45 











6 







5 

 9 

 5 











5 











1 



7 

 14 









4 



















3 













21 

 7 

 13 







2 















3 

 2 





1 

















1 





















