594 CHIH Pina 
be alive when replaced in water of ordinary temperature. It is safe 
to assume that the larva can live in water at the freezing point for a 
still greater length of time, if no other detrimental factors are involved. 
Light.— In order to minimize the influence of temperature, the experi- 
ment having to do with the effect of light was performed outdoors on 
a sunny afternoon in the latter part of October. The temperature on 
that afternoon registered 14° C. Twenty-two larvae were placed in a 
dish 14 centimeters long and 10 centimeters wide, containing water about 
2 centimeters deep. A piece of board covering about two-thirds of the 
dish was laid over the top to produce a shade. Under bright sunshine 
the larvae had crawled around in water, but about half an hour after the 
shade had been placed over the dish, fifteen of the larvae came under the 
shadow. The board was then removed, and the dish was slightly jarred 
in order that the larvae might be evenly distributed. When the shade 
was again replaced, similar results happened within half an hour. This 
time six larvae were crawling in the light but all the others had gone into 
the shade. Then the dish was turned around and the formerly shaded 
part was now exposed to light. At the end of half an hour twelve 
larvae came quite to the end of the shaded part, two stopped at the 
middle, while the others were entangled together and with some plant 
materials in the water, and were moving back and forth at the border 
between the light and the shade. According to the behavior of the 
majority there seemed to be a general tendency among the larvae to evade 
light. 
At noontime during midsummer the larvae living in the overflowed 
areas were found hiding themselves under the floating scums. In the pools 
they stayed at the bottom or at a considerable distance below the surface. 
This may have been due to the excessive heat from the direct rays of the 
sun so that light alone may not have been solely responsible. In the 
latter part of October, over a great part of the overflowed areas numerous 
larvae were aggregated along the side where the water was exposed to 
the morning sunshine, while at the other side, where the delta deposit 
produced an extensive shadow over the water, very few were found. The 
larvae were attracted probably by the warmer temperature in the morn- 
ing, after they had endured a frosty night. 
Desiccation.—The larva can stay out of water for a considerable time, 
provided the soil retains enough moisture. In midsummer, when hot 
