96 



ECONOMIC ENTOMOLOGY 



The Neuropteroida Group 



Certain orders of aquatic insects have a superficial resemblance 

 of wing venation, and were formerly grouped together into one order, 

 the Neuroptera. Of the six main Orders 

 three have incomplete metamorphosis, viz., 

 Plecoptera, Ephemerida and Odonata, and 

 three complete metamorphosis, viz., Tri- 

 choptera, Neuroptera and Mecoptera. 



It is probable, therefore, that the first 

 three orders are not so highly evolved as the 

 last three. The former are lower than the 

 Orthoptera, while the latter are higher and 

 come between the Hemiptera and the 

 Lepidoptera. 



Chief Orders: ^ 



The Neuropteroida (or nerve-winged) group of 

 insects includes six main orders which may be sepa- 

 rated as follows: 



A. Lower wings folded in plaits under the 

 upper. 

 B. Wings covered with hairs; tarsi 

 5-jointed ; metamorphosis complete. — 

 Trichoptera (Caddice-fiies) . 

 BB. Wings not covered with hairs. 

 C. Tarsi 5-jointed; wings equal and with many veins and cross-veins; 

 mouth-parts well developed; metamorphosis complete. — Neurop- 

 tera (Dobson flies, Aphis lions, etc.). 

 CC. Tarsi 3-jointed; hind wings larger than fore-wings; with caudal 

 filaments; biting mouth-parts poorly developed; metamorphosis 

 incomplete.- — Plecoptera (Stone-flies) (Fig. 54). 

 AA. Lower wings not folded under the upper. 



B. Head prolonged into a beak; antennae long; metamorphosis com- 

 plete. — Mecoptera (Scorpion-flies) . 

 BB. Head not prolonged into a beak; antennae inconspicuous; metamor- 

 phosis incomplete. 



1 Handlirsch arranges these orders into groups as follows: 



Odonata Sub-class Libelluloidea. 



Plecoptera (Ephemerida) Sub-class Ephemeroidea. 



Plecoptera Sub-class Perloidea. 



Neuroptera | 



Megaloptera [ Sub-class Neuropteroidea. 



Raphidioidea J 

 Panorpatae ) 



Trichoptera [ Sub-class Panorpoidea. 



Lepidoptera 



Fig. si. — The snow 

 flea {A chorules nivi- 

 cola). Enlarged greatly. 

 {After Folsom.) 



