Mosquitoes 



99 



On account of the various habits of both the 

 larvae and adults it will never be possible for any 

 natural enemy or group of natural enemies effect- 

 ively to control the mosquitoes of any region, but 

 as certain of them are important as helpers they 

 deserve to be mentioned. 



ENEMIES OF THE ADULTS 



Birds devour a few mosquitoes, the night-flying 

 forms being particularly serviceable, but the num- 

 ber thus destroyed is probably so small as to be of 

 little practical importance. 



The dragon-flies (Figs. 89, 90, 91) or mosquito 

 hawks have long been known as great enemies 

 of mosquitoes, and they certainly do destroy many 

 of them as they are hawking about places where 

 mosquitoes abound. Dr. J. B. Smith of New Jer- 

 sey very much doubts their efficiency, but obser- 

 vations made by other scientific men would seem 

 to indicate that they often devour large numbers 

 of mosquitoes during the course of the day and 

 evening. 



Spiders and toads destroy a few mosquitoes each 

 night. Certain external and internal parasites de- 

 stroy a few more, but the sum total of all of these 

 agencies is probably not very considerable, for 

 while the adults may have several natural enemies 



