48 
only from Ithaca, N. Y., through the kindness of Prof. J. H. Com- 
stock. Another species, A. fuscus, is said by Osten Sacken to occur 
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 
destroying the mosquito and the house fly, especially 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 ws. 
Mosquitoes. The Lamborn prize essays.” The essays were all excel- 
lent. Here, however, they are mentioned, by 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 larvee, feed upon the larve and pupz 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 larve and pupz 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 Hydrophilide eats hundreds of 
other insects in the course of its existence, and the larvee 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 by 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, 
