8o AGRICULTURAL EXPERIMENT STATION. 



may devour a great many ; but they are not factors of great 

 importance in the practical control. 



Of course, this limitation applies to insects also, and none have 

 a g-reater or more undeserved reputation as moscjuito destroyers 

 than the "dragon-flies," "devil's darning needles," "snake doctors" 

 or "spindles," to whom the name "mosquito hawks" has been 

 quite unjustifiably attached. "Dragon-flies" are as essentially 

 creatures of the day as the mosquitoes are of the night. They 

 frequent the open spaces around ponds and streams, the roads 

 and fields in the full sunlight, and never by any chance the wood- 

 land or those dark moist recesses where their supposed prey 

 spends the daylight hours. They are creatures of the air, ever 

 on the wing when the sun shines and resting in the open on 

 exposed twigs and branches. In the early evening, as soon as 

 the shadows lengthen, a more retired spot is sought, and long 

 before the mosquitoes find it pleasant to move, the "mosquito 

 hawks" are fast asleep. Who ever saw a "dragon-fly" hunting 

 among the grass for moscjuitoes? and who has ever seen 

 "dragon-flies" systematically hunting mosquitoes at any time? 

 The "dragon-fly" captures its prey while on the wing, holds it 

 with the legs, which all converge to one point for this especial 

 purpose, and devours it while in flight. The mouth of the 

 "dragon-fly" is so arranged that the food must be presented to 

 and practically pushed into it. It would be an impossibility for 

 the insect to crawl among the grass and pick up with its mouth 

 parts a creature resting on the blade or hidden near the ground. 

 I have watched "dragon-flies" t»f different species for many 

 minutes at many times, but never saw one of them capture a 

 mosquito — which is no direct proof, of course, that they may 

 not do so. I have been on the salt marsh when mosquitoes were 

 busy about me and where "dragon-flies" were rather plentiful, 

 but though they came quite close to me, none made the least 

 attempt to capture any of my attendants. I am sorry to dis- 

 credit a popular belief, but I cannot find as the result of my 

 observations that "dragon-flies" in the adult stage materially 

 lessen the mosquito supply. 



The effective species are those birds and beasts that begin to 

 fly and prowl about in the twilight, when the mosquito itself is 

 awing. Birds like the whip-poor-will, which add character to 

 the hour and place, or like the "night-hawk," which flies swiftly 

 and silently where mosquitoes at that time abound. Animals 

 like the toad, which is as silent and adroit as it looks clumsy, and 

 which picks up mosquitoes in quantity while waiting for some- 

 thing more substantial. Of predatory insects there are many 



