4o 



Recognition characters of some of the commoner 



Single distinctive characters 



1. Forms in which the immature stages (commonly known as nymphs) 

 and are plainly visible upon the back. 



2. Forms in which the immature stages differ very greatly from the adults 

 internally and not visible from the outside, and having the legs shorter, rudi- 



Common Name 



Water-moths 



Caddis-worms 



Orl-nies 



Dobsons 



Water-beetles 

 True flies 



Order 



Lepidoptera 



Trichoptera 

 Neuroptera 

 Neuroptera 



Coleoptera 

 Diptera 



Legs 



3 pairs of minute 

 jointed legs followed 

 by a number of pairs 

 of fleshy prolegs 



3 pairs rather long 



3 pairs shorter 

 3 pairs 



3 pairs 

 wanting 



Gills 



of numerous soft white 

 filaments, or entirely 

 wanting 



variable or wanting 



7 pairs of long, lateral 

 filaments 



tufted at base of lateral 

 filaments, or want- 

 ing 



usually wanting 



usually only a bunch 

 of retractile anal gills 



3. Further characters of some common dipterous larvae. These are distin- 



