THE NYMPHA 



This stage in the tropics usually lasts about forty- 

 eight hours. When first the larval coat is cast the 

 nymph is light in colour, and may be readily over- 

 looked. Later, the nymph becomes darker, and 

 towards the end and immediately prior to the emer- 

 gence of the imago, silvery patches due to collections 

 of air are seen beneath the cuticle. 



Pupae taken out of the water and kept on moist 

 blotting-paper will still develop into winged insects 

 (Nuttall and Shipley). 



Egg to Imago. The developmental cycle for A. maculi-pennis 

 is about thirty days at a temperature of 2O-25 C. In the tropics 

 it is much less. Thus the minimum time for Ce. argyrotarsis, M. rossi, 

 M. culicifacies is fourteen days. 



Permanent preparations of the nymph are made 

 in the same way as those of the larva (p. 191). Place 

 two strips of cardboard under the coverglass. 



