2gg Philippine Journal of Science i»i» 



of assembling and dispersing and the scant half hour during 

 which the swarms were definite enough to be called such, might 

 indicate a precise purpose and an exact time of the day for 

 carrying out that purpose. 



On this afternoon a very mild breeze was blowing, but there 

 were occasional gusts which seemed to stimulate the mosquitoes 

 to greater activity and to cause them to bunch together with a 

 very quick movement, as players in a foot-ball scrimmage. If 

 I stood perfectly still beneath a swarm, it came close to my 

 head; if, on the other hand, I even gently thrust my hand up- 

 ward, the Anophelines rose en masse away from it. 



During the whole time of swarming, two dragon flies were 

 darting in and out of the swarms, and each quite obviously 

 caught a mosquito every time. 



The two remarkable features of these occurrences are that 

 the insects are Anophelines, and that they were swarming 

 during a very stiff breeze on each occasion. Many observers, 

 entomologists as well as non-entomologists, have maintained 

 that high winds are inimical to the welfare of the mosquito, 

 and that the insects will not venture forth when strong winds 

 are blowing. It has been repeatedly stated that when mosqui- 

 toes are found at a distance from water, they have been wafted 

 thither by gentle breezes. G. M. Giles, says: 7 



* * * as naturalists are generally agreed that gnats cannot travel 

 to any considerable distance, it follows that food both for adult and larva 

 must be obtained within a limited area, for mosquitoes cannot and do not 

 fly far. It is impossible to fix any absolute limit to their powers in this 

 respect, but it may be safely asserted that few individuals ever stray 

 much more than a quarter of a mile from the pool in which their larval 

 youth was passed, and the great majority never travel further than the 

 nearest shady spot. Nor, in spite of popular beliefs to the contrary, can 

 they be carried far by the wind. Mosquitoes, indeed, exhibit a well- 

 founded, instinctive dread of boisterous weather, and will not leave shelter 

 in a high wind. Those accidentally carried away are, I am inclined to 

 think, rapidly disabled. 



Another reason that makes it impossible for Mosquitoes to be carried 

 overseas any considerable distance by the wind is that, whatever may be 

 the rate of travel that they can bear without injury, the entire journey 

 must be made at night, for in tropical regions shelter from the sun during 

 the day is a matter of life and death to a Mosquito * * *. 



For these reasons, we may, I think reject, as having no foundation in 

 fact, such popular beliefs as that the swarms of Mosquitoes that sometimes 

 appear on the Persian coast, have been carried by the wind 200 miles 

 across the Gulf from the Arabian shore; albeit you must be prepared to 

 hear this belief quoted as an established fact, even by European residents. 



'Gnats or Mosquitoes, ed. 2. London (1902) 112, 113. 



