MOSQUITO BIOLOGY 46 



during the year confirmed this conclusion, and a series of laboratory 

 experiments with sods brought to New Brunswick showed that the eggs 

 might survive an almost complete drying out ; not for a day or a week, 

 but for months ; hatching promptly as soon as they became water cov- 

 ered. 



Mr. Viereck's experiments conducted at the Cape May Station in 

 1903, give the following conclusions : 



July 24, placed one dozen gravid females into each one of two quart 

 jars, in which bottom was thinly covered with marsh sod. July 25, some 

 were dead, only three females had abdomen yet distended. July 27, 

 only three living specimens remained, in these the abdomen was col- 

 lapsed. July 28, all were dead. July 30, the sod was examined and black 

 eggs were found, most of which must have been laid during the night 

 of July 24. The eggs were evidently white when laid and became black 

 subsequently. It rained during the night of July 29, and water covered 

 the bottom of one of the jars in which baby wrigglers were found on 

 the thirtieth. These lived until August 5, when only a few survived. On 

 the sixth, a new lot of babies hatched and some sound eggs yet remained 

 in the sod. Only a few eggs in this series collapsed. 



August 2, prepared two one-quart jars with moist lint at the bottom 

 and two others with lint covered with moist marsh mud, which had been 

 sterilized to make certain no live eggs were introduced. Ten gravid 

 females were placed in each and oviposition began while the jars were 

 yet under observation. One specimen extended its ovipositor, darted 

 its end into the sod until it found a suitable place, then laid six eggs, 

 one after the other, and flew off. Another placed fifty-two eggs, one by 

 one, in an irregular row about an inch long, in one continuous laying. 

 A third took great pains hunting up a suitable place by darting its 

 ovipositor in many directions before placing each egg. At 6:00 p.m., 

 and a few minutes after, an injured female laid all its eggs in a heap, 

 one by one, but rapidly. At 7 :30 p.m., those first laid were black, the 

 rest assuming a gray color and becoming black from the end first laid 

 to the end last to appear. Some of the eggs were placed and kept in a 

 dark place, but these blackened as rapidly as did those kept in the light. 

 Eggs taken from the ovary of a female ready to lay, perfect in size 

 and form, failed to darken in color, and collapsed. 



August 3, eggs of this second series were placed in four jars and 

 covered with sea water 100 per cent, sea water fifty per cent, sea water 

 twenty-five per cent, and pure artesian spring water. No larvae had 

 hatched in any of these jars August 6, after being covered for seventy- 

 two hours, and the water was then poured off, leaving only a little mois- 



