II 



FLIES WITH AQUATIC LARV^ 



in which the whole of the aquatic Hfe of the SimuHum 

 is passed. An inactive and exposed pupa, hke that 

 of Chironomus, may fare well enough on the soft 



ni/Mm ?m 



•X.JOO 







Fig. 64.— Simulium. A, larva in outline, with salivary glands. B, coronet of hooks 

 at tail-end of larva. C, part of silken cocoon of pupa, showing its interwoven 

 fibres, the product of the salivary glands. 



muddy bottom of a slow stream, but such a pupa 

 would be swept away in a moment by the currents 

 in which Simulium is most at home. Before pupa- 

 tion the Insect constructs for itself a kind of nest, 



