MEDITERRANEAN FRUIT FLY IN HAWAII. 9 



pupating in the corners of the fruit containers and in secluded spots 

 about the deck. It would have been quite possible for larvae thus 

 emerging to have completed their development during the days re- 

 quired for the voyage between Sydney and Honolulu and emerged as 

 adults while the ship lay at anchor at Honolulu within several hun- 

 dred yards of host fruit trees. As the Mediterranean fruit fly did not 

 become established about Sydney and the eastern portion of Aus- 

 tralia until 1898-1907, its establishment about Honolulu between 

 1907 and 1908 came as a natural sequence. This is most forcibly 

 brought to the attention of those interested in horticultural devel- 

 opment when they appreciate the frequency with which this pest has 

 attempted to bridge the Pacific between Honolulu and San Francisco 

 since its establishment at Honolulu, as indicated by the interception 

 of infested fruit at San Francisco by officers of the Federal Horti- 

 cultural Board. 



CONDITIONS FAVORABLE TO ESTABLISHMENT IN THE HAWAIIAN 



ISLANDS. 



CLIMATIC CONDITIONS IN HONOLULU. 



The climate of the littoral regions of Hawaii, and up to an elevation 

 of 1,500 feet, is most favorable to the establishment and rapid increase 

 of G. capitata. At Honolulu the temperature very rarely drops as 

 low as 58° F., and then only for a few hours during one or two nights 

 in the year. The data in Table I, taken from the monthly meteoro- 

 logical summaries of the U. S. Weather Bureau at Honolulu for 1914, 

 are given as a fairly reliable guide to the ranges in temperature 

 throughout littoral Hawaii. 



Table I. — Temperature and relative humidity at Honolulu during 1914- 



Month. 



Temperature. 



Maxi- 

 mum. 



Mini- 

 mum. 



Daily range. 



Maxi- 

 mum. 



Mini- 

 mum. 



Aver- 



Mean at 1 



6 a. 

 m. 



2 p. 



9 p. 



Mean 



of 

 maxi- 

 mum 

 and 

 mini- 

 mum. 



Relative hu- 

 midity. 



Maxi- 

 mum. 



Mini- 

 mum, 



Mean. 



January. . . 

 February . 



March 



April 



May 



June 



July 



August 



September 

 October. . . 

 November 

 December. 



"F. 

 18 

 14 

 15 

 15 

 14 

 12 

 15 

 12 

 12 

 14 

 13 

 14 



"F. 



10 

 11.4 

 10.5 

 10.7 

 9.4 

 9.1 

 9.2 

 9.1 

 8.1 

 9.4 

 10.2 

 10.7 



"F. 



67.4 

 66.2 

 67.5 

 68.6 

 72.6 

 74.0 

 75.2 

 76.0 

 75.9 

 73.6 

 71.4 

 67.6 



"F. 



74.0 

 72.4 

 74.8 

 75.8 

 79.9 

 80.4 

 81.5 

 81.4 

 80.6 

 79.7 

 77.2 

 74.3 



°F. 



68.9 

 68.3 

 89.6 

 70.9 

 74.6 

 76.0 

 76.3 

 76.8 

 77.0 

 75.1 

 72.9 

 69.7 



"F. 



■69.1 

 71.4 

 70.9 

 72.5 

 74.3 

 76.6 

 78.4 

 79.0 

 78.7 

 77.0 

 74.6 

 71.1 



P.ct. 

 83 

 82 

 86 

 81 

 82 

 80 

 81 

 80 

 85 

 74 

 85 



P.ct. 

 50 

 52 

 53 

 52 

 56 

 58 

 62 

 58 

 62 

 60 

 52 

 60 



P.ct. 

 66.4 

 70.9 

 68.6 

 68.7 

 70.1 

 68.8 

 69.6 

 69.2 

 71.4 

 68.0 

 70.5 

 72.7 



1 Compiled from 1914 and 1915 data, taken from the 1916 Hawaiian Annual. 



2 The normal mean for January is 71.1° F. 



