48 



onl}^ from Ithaca, N. Y., throug-h the kindness of Prof. J. H, Com 

 stock. Another species, A. fuscas^ is said by Osteu Sacken to occui 

 at Cambridge, Mass. 



THE NATURAL ENEMIES OF MOSQUITOES. 



The late Dr. Robert H. Lamborn, of New York and Philadelphia, 

 while engaged a number of years ago in building the Lake Superior 

 and Mississippi Railroad, fell in with a great many mosquitoes. He 

 often, "with a sentiment of gratitude." as he expressed it, looked 

 through his mosquito veil at the dragon flies which collected in the 

 open spaces among the pine trees. "They darted from side to side, 

 like swallows in a meadow, but with amazing rapidity, and at every 

 turn a mosquito 'ceased from troubling.'" This gave Dr. Lamborn 

 the idea that perhaps dragon flies might be domesticated and utilized 

 to destroy mosquitoes along the New Jersey coast and elsewhere; and 

 so he offered prizes for the three best essays regarding methods of 

 destro\dng the mosquito and the house fl}^, especiall}^ designating the 

 dragon fly for careful investigation. The successful essays — by Mrs. 

 C. B. Aaron, Mr. A. C. Weeks, and Mr. William Beutenmiiller — were 

 published by Dr. Lamborn in a volume entitled " Dragon-Flies r.y. 

 Mosquitoes. The Lamborn prize essays." The essays were all excel- 

 lent. Here, however, they are mentioned, bj^ the way, in connection 

 with the group of the best-known natural enemies of mosquitoes, 

 namely, the dragon flies. It is needless to say that none of the essays 

 were able to solve the problem of a practical breeding, on a large 

 scale, of dragon flies for mosquito extermination, and, in fact, the 

 whole subject of the natural enemies of the mosquito is of little 

 practical importance. It is simply a matter of general interest. 

 Dragon flies, as adults, feed upon adult mosquitoes, just as they will 

 upon all other insects which they are able to capture and devour. 

 Dragon flies, as larva% feed upon the larvae and pupse of mosquitoes, 

 although other and larger and less active aquatic insects and small fish 

 form the bulk of their food. 



The extreme activity of both larvffi and pup^e of mosquitoes is a 

 necessary factor in their struggle for existence, since stagnant pools 

 of water fairly swarm with predatory animal life. The larva of one 

 of the water beetles of the family Hydrophilidffi eats hundreds of 

 other insects in the course of its existence, and thelarva^ of mosquitoes 

 do not escape entirely, although by their extreme activity they stand 

 a better chance than do other more sluggish species. A small pool of 

 water on the Department grounds at Washington is situated near a 

 manure pile, and the water is colored dark brown b}^ the drainage 

 from the manure. The pool is kept by Mr. Saunders, the superin- 

 tendent of the grounds, for the purpose of securing manure water 

 for some of his plants. It is, at all times through the summer, 



