23 



the pointed ellipse, convex below and concave above, all the eggs per- 

 pendicular, in to 13 longitudinal rows, with from 3 or 4: to 40 eggs in 

 a row. The number of eggs in each batch varies from 200 to 400. As 

 seen from above the egg mass is gray brown; from below, silvery 

 white, the latter appearance being due to the air Him. It seems 

 impossible to wet these egg masses. They may be pushed under 

 water, but bob up apparently as dry as ever. The egg mass separates 

 rather regularl}', and the eggs are not stuck together very firmly. 

 After the}" have hatched the mass Avill disintegrate in a few days, even 

 in perfectly still water. 



The individual eggs are 0.7 mm. in length and 0.16 mm. in diameter 

 at the base. They are slender, broader and blunt at bottom, slenderer 

 and somewhat pointed at tip. The tip is always dark grayish brown in 



I 



Fig. 1. — Culexpungens: Egg mass, witli englarged eggs at left and young larvie below — enlarged 



(original) . 



color, while the rest of the egg is dirty white. Repeated observations 

 show that the eggs hatch, under advantageous conditions, certainly 

 as soon as sixteen hours. Water ])uckets containing no egg masses, 

 placed out at night, were found to contain egg masses at 8 o'clock in 

 the morning, which, as above stated, were probably laid in the early 

 morning, ])efore daylight. These eggs, the third week in May, began 

 to hatch quite regularly at 2 o'clock in the afternoon of the same day 

 on warm days. In cooler weather they sometimes remained unhatched 

 until the second da}^ If we apply the evadence of Eui'opean ol)servers 

 to this species, the period of the egg state may be under twelve hours; 

 but there is a possibility that they are laid earlier in the night, which 

 accoimts for the fact that sixteen hours is the shortest period which we 

 can definitely mention. 



