52 



BULLETIN 536, U. S. DEPARTMENT OF AGRICULTURE. 



placed in storage at 26° to 30° F. when one day old, and held at this 

 temperature for 7 days, hatched three days after removal, or 11 

 days after deposition. 



Table XIII. — Duration of the egg stage of the Mediterranean fruit fly under low tem- 

 perature conditions. 



Number of 

 eggs under 

 observation. 



Eggs deposited. 



Cold-storage dates. 



Dates of 

 hatching. 



Num- 

 ber of 

 days in 

 storage. 



Length 

 of egg 

 stage. 



Temperatures. 



Inward. 



Outward. 



Range 



in 

 storage. 



Mean 

 outside 

 storage. 



10 

 4 



July 6, 1913 



do 



July 7 

 ...do 



July 8 

 July 9 

 ...do 



July 9 

 July 10 

 July 12 



...do 



Nov. 10 

 July 9 

 Nov. 14 

 Sept. 29 

 Oct. 2 

 Oct. 7 

 Sept. 19 

 Sept. 21 

 Nov. 28 

 Dec. 1 

 July 9 

 July 12 

 July 18 

 Aug. 4 

 June 30 

 July 2 

 July 6 

 July 10 

 July 15 

 July 18 

 July 20 

 Feb. 28 

 Mar. 15 

 Mar. 8 

 Aug. 24 

 Aug. 23 

 Aug. 31 

 July 20 

 July 24 

 Sept. 16 



Feb. 27 

 Mar. 6 



1 



2 



2 



1 



4 



6 



7 



2 



4 



9 



8 



8 



8 



10 



3 



4 



11 



14 



3 



3 



8 



11 



17 



20 



20 



14 



19 



22 



7 



7 



14 



4 



7 



7 



3 



4 



6 



6 



' 7 



9 



11 



4 



7 



12 



12 



14 



12 



15 



5 



8 



14 



18 



5 



7 



11 



15 



20 



23 



25 



16-17 



21-22 



24-25 



8-9 



7-8 



14-15 



4-5 



7-8 



7 



17-18 

 14 



26-30 

 26-30 

 26-30 

 26-30 

 26-30 

 26-30 

 26-30 

 32 

 32 

 32 

 33-34 

 33-34 

 36 

 36 

 33-38 

 33-38 

 33-38 

 33-38 

 38-45 

 38-45 

 38-45 

 3845 

 38-45 

 38-45 

 38-45 

 48-53 

 48-53 

 48-53 

 54-57 

 54-57 

 54-57 

 59-62 

 59-62 

 60-64 



* 30-62 

 639-89 



"F. 



78 

 78 



1 



do 



...do 



...do 



78 



2 



...do 



July 8 

 Nov. 8 

 July 8 

 Nov. 11 

 Sept. 28 

 Sept. 30 

 Oct. 5 

 Sept. 17 



...do 



Nov. 25 

 Nov. 27 

 July 8 

 July 9 

 July 16 

 Aug. 1 

 June 30 



...do 



July 5 

 July 8 

 July 14 

 July 17 



...do 



78 



'388 



6 



1 



520 



216 



Nov. 3,1914 



June 30, 1913 



Nov. 3, 1914 



Sept. 25, 1914 

 do 



Nov. 4 

 July 2 

 Nov. 4 

 Sept. 26 

 ...do 



76.5 



77 



76.5 



77.6 



77.6 



1 



do 



...do 



77.5 



21 



4 



242 



5 



Sept. 7, 1914 



Nov. 16, 1914 



do 



Sept. 9 



do 



Nov. 17 

 ...do 



79.5 

 78.9 

 69.5 

 70.4 



5 

 11 



July 4, 1913 



July 5 

 . ..do 



77.2 

 77.4 



13 

 1 

 1 



3 



do 



July 17, 1913 



June 25, 1913 



do 



...do 



July 18 

 June 27 



...do 



78.2 

 78.9 

 77.8 

 77.6 



7 



do 



...do 



77.3 



1 



do 



...do 



77.4 



6 



do 



...do 



77.7 



1 



...do 



...do 



77.9 



1 



do 



Feb. 11-12, 1915... 



do 



do 



...do 



77.8 



20 

 11 

 1 



Feb. 12 

 ...do 

 ...do 



Feb. 26 

 Mar. 3 

 Mar. 6 

 Aug. 23 



(') 

 Aug. 30 



0) 

 July 23 



(0 

 Feb. 25 



69.8 

 70.5 

 70.6 



19 

 5 

 1 



Aug. 1.5-16, 1914... 



do„ 



do 



Aug. 16 



...do 



...do 



79.1 

 79.1 

 79.1 



32 



6 



July 15-16, 1914.... 

 do 



July 16 

 ...do 



79.5 

 79.5 



172 



23 

 131 



Sept. 9, 11 a. m. to 



2 p. m. 

 Feb. 9-10, 1915.... 

 Feb. 20, 1915 



Sept. 9, 

 3 p.m. 



2 Feb. 11 



3 Feb. 21 



79.2 



69.4 

 67.8 









1,720 





1 Fruit not removed. Eggs hatched in storage. 



2 Not placed in cold storage,but exposed to normal tmperatures at summit of Mount Hualalai, 8,200 feet 

 elevation. 



3 Not placed in cold storage, but exposed to normal temperature at Puulehua, about 4,500 feet elevation. 

 « Mean temperature about 46° F. 



6 Mean temperature about 70° F. 



These data, together with those recorded in Table XIII, demon- 

 strate the great variation, from a fruit-fly standpoint, in the duration 

 of the egg stage. 



THE LARVA. 



DESCRIPTION. 



A clear idea of the general shape of the larva or maggot of the 

 Mediterranean fruit fly can be gained by reference to text figures 7 

 and 8, and'Plate XIII, figure 1. When first hatched from the egg, 

 the larva is about 1 mm. long but increases in size to from 7-8 mm. 

 long when full grown. Each larva passes through three well-defined 



