CHAPTEE XX 



INSECTA (cmtinued) 



Order V. : Neuuoptera 

 (Dragon-flies, May-flies, Caddis-flies, etc.) 



All the Neuroptera, or " nerve-winged " insects (Gk. neuron, a 

 nerve ; pteron, a wing), have in the adult stage two pairs 

 of well - developed membranous wings, with conspicuous 

 " nervures " forming a network throughout them. The 

 mouth -parts are adapted for biting. The metamorphosis 

 varies in the different families which constitute the order. 

 In all it is great, but the change from larva to imago may- 

 take place without a resting pupal stage, as in Dragon-flies, 

 or with a well-marked pupal rest, as in Caddis-flies. 



Family 1 : Odontata (Dragon-fi-ies) 



This family of the Dragon-flies includes forms all of which 

 undergo an incomplete metamorphosis, though the change of 

 form at the last moult is very great. The larvae are aquatic 

 and carnivorous, and have a curious modification of the 

 lower lip for catching their prey. The perfect insects are 

 also carnivorous; they have very small inconspicuous antennae; 

 the segments of the thorax are much thickened vertically, and 

 slope from below backwards, so that the legs are always 

 attached in front of the wings. The wings are usually 

 transparent, and have a very complex network of nervures, 

 which differs in certain points in the different sub-orders ; in 

 all of them the front margin of each wing has, near the 

 middle, a slight irregularity, looking as if it had been broken 

 at this point ; this is called the " node " of the wing. 



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