clxxxviii Proposed Division of Neuroptera 



The Agrionina may be divided according to the subjoined formula. 



Those in which the continuity of the costal mar- 

 gin of the wing is interrupted or broken near 

 the base, and the costal cells between this 

 break and the base have scarcely any transverse 



veins, Agrionid,e, Newm. 



non Leach, 



Those in which the continuity of the costal margin 

 of the wing is interrupted or broken at more 

 than a third of the distance from the base to- 

 wards the tip, and the costal cells between this 

 break and the base have very numerous and re- 

 gular transverse veins, Calepterycid^e, Newm. 



Characters of Libellulina. 



Larva aquatic, breathing by means of an internal abdominal appa- 

 ratus, which appears to possess the power of abstracting oxygen 

 from water, which is subsequently expelled through the anal 

 aperture with a jerk ; it has rather short filiform antenna, cor- 

 neous mandibles, and a jointed porrected labium; its body is 

 rather robust, and gradually attenuated towards the caudal ex- 

 tremity, which is furnished with three flattened appendages : it 

 is carnivorous and excessively voracious. 



Pupa in figure very unlike the larva, short, obese, and somewhat 

 toad-like, its wing-cases large and conspicuous, the abdomen 

 turned up at the extremity, and furnished with short conical 

 appendages : habits entirely aquatic, carnivorous, voracious. 



Imago with very short and slender antennae, transverse, suhglohose, 

 exserted head generally occupied exclusively with the enormous 

 approximate eyes, and powerful, fully developed mouth, 3 ocelli, 

 atrophied prothorax, elongate variously formed abdomen ; 4 

 reticulated wings, nearly alike but not quite so, the shortest dia- 

 meter of the fore, and the longest diameter of the hind wings is 

 near the base ; all of them are porrected separately and hori- 

 zontally when at rest, and never meet back to back above the 

 abdomen; their flight is powerful, rapid, and enduring, their 

 lives are spent almost entirely on the wing, hawking for insects, 

 especially over pools and in damp woods ; they are excessively 

 voracious and predatory, seizing their prey on the wing, and 

 settling for the purpose of devouring it : their tarsi are 3-jointed. 



