164 MOSQUITOES 



number of the western salamander {Diemyd]flus torostts 

 Escli.) wliicli were liberated in the upper part of the 

 Makiki stream in the hope of reducing the large number 

 of mosquitoes breeding everywhere in small i30ols and 

 taro fields. He kept two of these salamanders for sev- 

 eral weeks in an open tank, and they devoured, and kept 

 the water free from, the mosquito larvae that bred there. 

 While hundreds of the newly hatched mosquito larvae 

 could always be observed, none of them ever reached full 

 growth. Mr. Koebele says, " It is to be greatly desired 

 that this valuable batrachian will increase to such num- 

 bers as to be able to help us keep in check the most 

 troublesome insect on these islands." 



Then there are many predatory insects which feed upon 

 mosquitoes. The late Dr. R. H. Lamborn, of New York 

 and Philadelphia, was so impressed with the voracity 

 of dragon-flies that he offered a series of prizes for the 

 three best essays regarding the methods of destro}^- 

 ing mosquitoes and house-flies, especially designating 

 the dragon-fl}^ for careful investigation. The prizes were 

 awarded and the successful essays were published in an 

 entertaining volume entitled " Dragon-flies vs. Mosqui- 

 toes. The Lamborn Prize Essays." None of the essays 

 were able to solve the problem of the practical breeding 

 on a large scale of dragon-flies for mosquito extermina- 

 tion, and, in fact, the insect enemies of the mosquitoes 

 cannot be practically handled. Dragon-flies as larvae 

 feed upon mosquito larvae, just as they feed upon all 

 other aquatic insects and even upon small fish. As 

 winged adults they capture mosquitoes on the wing, just 



