89 



2. The extreme length and slenderness of 

 the syphon tube (Fig. 22). 



Psorophora. — The larvae are large, half-an- 

 inch in length. They are extremely cannabalistic. 



The Nymph 



The nymphae of mosquitoes are extremely 

 characteristic bodies. Wherever a number of 

 fully-developed larvae are found there will gene- 

 rally also be seen numbers of bulbous comma- 

 shaped creatures, having a large globular body 

 (head and thorax) and a small tail, kept more or 

 less tucked in beneath. When disturbed they 

 dart downwards with great speed, but very soon 

 reappear at the surface. 



Fig. 24. Nymphae of an Anopheline and Culex 



Nymphs are not so easily seen in pools as 

 larvae. 



The differences in the nymphae of different 

 genera of the Culicidae is not nearly so great as in 

 the case of the larvae. 



