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. 



Inward. Outward. 



Dates of 

 hatching 



Num- 

 ber of 

 days in 

 storage. 



Length 

 of egg 

 stage. 



Temperatures. 



Range 



in 

 storage. 



Mean 

 outside 

 storage. 



6 



1 



520 



216 



1 



21 

 4 

 242 

 5 

 5 



11 



13 

 1 

 1 

 3 

 7 

 1 

 6 

 1 

 1 



20 



11 

 1 



19 

 5 

 1 



32 



6 



172 



131 



1,720 



July 6, 1913 



do 



do 



do 



Nov. 3, 1914 



June 30, 1913 



Nov. 3,1914 



Sept. 25, 1914 



do 



do 



Sept. 7, 1914 



do 



Nov. 16, 1914 



do 



Julv4, 1913 



do 



do 



July 17, 1913 



June 25, 1913 



do 



do 



do 



do 



do 



do 



Feb. 11-12, 1915.. 



do 



.... v do 



Aug. 15-16, 1914.. 



do 



do 



Julv 15-16, 1914... 

 .....do 



Sept. 9, 11 a. m. to 

 2 p. m. 



Feb. 9-10, 1915... 



Feb. 20, 1915 



July 

 ...do. 

 ...do. 

 ...do. 

 Nov. 

 July 

 Nov. 

 Sept, 

 ...do. 

 ...do. 

 Sept. 

 ...do. 

 Nov. 

 ...do. 

 July 

 ...do. 

 ...do. 

 July 

 June 

 ...do. 

 ...do. 

 ...do. 

 ...do. 

 ...do. 

 ...do. 

 Feb. 

 ...do. 

 ...do. 



July S 

 July 9 



..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 

 ... Julv 16 

 18 I Aug. 1 

 27 I June 30 



do 



... July 5 

 ...July 8 



Aug. 

 ..do. 

 ...do.. 

 Julv 

 ..do. 

 Sept, 

 3p. 



2 Feb. 



3 Feb. 



16 



July 



14 



Julv 



17 



...do. 





Feb. 



26 



Mar. 



3 



Mar. 



6 



Aug. 



23 



(M 





Aug. 



30 



0) 





July 



23 



( l ) 





Feb. 



25 







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 

 Julv 9 

 Julv 12 

 July 18 

 Aug. 4 

 June 30 

 July 2 

 July 6 

 July 10 

 Julv 15 

 Julv IS. 

 Julv 20 

 Feb. 28 

 Mar. 15 

 Mar. 8 

 Aug. 24 

 Aug. 23 

 AUg. 31 

 Julv 2€ 

 Julv 24 

 Sept. 16 



Feb. 27 

 Mar. 6 



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 



14-15 

 4-5 

 7-8 



17-18 

 14 



°F. 



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 

 3S-45 

 38-45 

 38-45 

 38-45 

 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 

 539-89 



78 



78 



76.5 



77 



76.5 



77.6 



77.6 



77.5 



79.5 



78.9 



69.5 



70.4 



77.2 



77.4 



78.2 



78.9 



77.8 



77.6 



77.3 



77.4 



77.7 



77.9 



77.8 



70.5 

 70.6 

 79.1 

 79.1 

 79.1 

 79.5 

 79.5 

 79.2 



67. 



» 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. 



4 Mean temperature about 46° F. 



5 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 



