16 
stopped he went to the place and found the mosquito larve all through 
the water as lively as ever, and they began to issue as adults about a 
week from that time. Again he discovered a place where the water 
had nearly dried up, and hundreds of mosquito larve were seen by 
him on the wet ground. Three days later it rained, and he found the 
larvee in the water as lively as ever. In the same way Mr. Benjamin 
S. Paschall, of Newfield, N. J., has communicated to us observations 
of his own which indicate to him a possibility that mosquitoes may 
breed in grass or moist earth. 
Experiments made at this office on a small scale in glass vessels 
have shown that the larve of Culex will exist for some little time in 
wet mud, and some of them will successfully transform after water 
has been added. In no case, however, were we able to revive larve 
in mud from which the water had been drawn off for more than forty- 
eight hours, and after twenty-four hours only.a small proportion of 
the larve revived. An interesting pool has been under observation 
during the present month. The pool contained a surface area of abcut 
24 square feet, and was fed entirely by rain water and surface drain- 
age, reaching a depth when full of about 1 foot. All through the sum- 
mer this pool is well stocked with mosquito larve. After a somewhat 
long drought the water was observed on July 18 to have evaporated 
almost entirely, a small puddle in the center of the cavity, containing 
only 3 or 4 cubic inches of water, remaining. It was dark in color, 
owing to the drainage from a manure pile near by, and to the casual 
observer showed no signs of life. The water in this little puddle was 
very shallow. On dipping in a coffee strainer, however, it was found 
to be literally massed with nearly full-grown mosquito larve, many 
hundreds of which had been brought together into this restricted 
place. The drying continued until there was almost no water left. 
On the night of the 20th came a heavy rain, followed with a still 
heavier one on the morning of the 22d. On the 23d the pool was 
found to be entirely full of water and to contain its usual stock of 
mosquito larvee. 
This may be safely said to indicate the usual habit of mosquito 
Jarve in evaporating pools. As the water gradually recedes toward 
the deepest portion of the excavation, the larve recede with it, con- 
centrating themselves at the deepest point, i. e., at the point where 
the moisture remains longest. Knowing as we do, then, that even 
in the absence of any free water the larvee will remain alive in moist 
mud for from twenty-four to forty-eight hours, it is evident that 
such a pool as the one described gradually drying would give the 
appearance of haying been practically dried up for some days before 
the last cubic inch of free water has entirely disappeared. The con- 
centration of many larve at this point in the manner which has been 
described could not fail to give rise to the belief that mosquito larve 
ee ee ie 
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