xxi INSECTA: NEUROPTERA 315 



segments, it bears seven pairs of jointed filamentous tracheal 

 gills, which curve upwards in life and give the larva a charac- 

 teristic appearance. The last abdominal segment is very 

 peculiar, being long and narrow and very pointed, and con- 

 taining two air-tubes, so that it acts as an extra tracheal gill. 

 When full grown, the larva is about one inch 

 lon S- It} then leaves tne water and hides itself 

 in the damp earth, sometimes several yards away. 

 Having formed a little cell for itself, it casts its skin and 

 exposes the quiescent pupa, with wing rudiments now ap- 

 parent. The wings and legs of the pupa are free from the 

 body, though enclosed in a special skin which is shed later. 

 This stage lasts two or three weeks ; then the fly emerges, 

 creeps up some object near by to dry its wings, and soon takes 

 to flight, never, however, going far from its native spot. 



Family 5 : CHRYSOPIDES (LACEWING-FLIES) 



The Chrysopides form another subdivision of the 

 Neuroptera, resembling the Alder-flies in having a complete 

 metamorphosis, with a quiescent pupal stage in which the 

 wings become for the first time apparent, but differing from 

 them in having much more delicate bodies and transparent, 

 lightly veined wings ; also they are entirely terrestrial, the 

 larvae inhabiting land plants and feeding on green-fly. 



The Gold-eyed Lace-fly (Chrysopa vulgar is). 



These flies have a rather thin small body, with a relatively 

 long abdomen. They are easily recognised by their long 

 antennae, and their four similar and very delicate transparent 

 wings, which when at rest roof over the body as in Fig. 238, i. 

 Both body and wings are of a pale-green colour, and the eyes 

 are brilliant and metallic-looking. 



The eggs are peculiar, for each is borne at 

 gss ' the tip of a stalk several times the length of the 

 egg itself ; clusters of them are frequently to be found hang- 

 ing from a leaf of lime or rose. Sometimes the egg stalks 

 are intertwined, so that there is a little bunch of eggs 

 (Fig. 238, A) ; sometimes each stands alone. 



