Aquatic Insects 113 



method of emergence is peculiar and 

 suggests a gymnastic display. These 

 larvae do not possess lateral tracheal gills, 

 but have terminal respiratory organs 

 that vary in the two types. Dragon- 

 flies are feared as well as admired, for 

 some country people firmly believe that 

 they can sting ; in some districts, in 

 fact, they are known as " horse-stingers." 

 This belief is entirely erroneous, as these 

 beautiful insects are quite incapable of 

 inflicting injury. 



Among the true flies (Diptera) are 

 several interesting species that have 

 aquatic larvae. Pre-eminent among these 

 are the members of the mosquito and 

 gnat tribe. Many of these are too well 

 known to need much description, as they 

 have forced themselves on man's notice 

 in a very unpleasant manner. The eggs 

 of mosquitoes are in some cases laid on 

 the surface of the water, either singly or 

 in masses known as egg-rafts, or are 



H 



