CLASSIFICATION OF INSECTS. 247 



805. Pearl-flies (Perlites). Larva with long, 

 filiform, multi- articulate antennae ; strong, cor- 

 neous, masticatory mandibles ; telum furnished 

 with two long, setiform appendages ; active, 

 carnivorous, aquatic. Pupa isomorphous. Imago 

 with long, filiform, multi-articulate antennee ; 

 strong, corneous, masticatory mandihles ; wings 

 fully and equally developed, reticulated, recum- 

 bent ; the hind wings folded ; tarsi three-jointed. 

 Inhabits the banks of running waters, and is a 

 very favourite food of fish ; flight nocturnal. 

 Perla, Isogemis, Nemoura. 



806. Snake-flies {liaphidiites). Larva with 

 filiform antennae, and corneous, masticatory man- 

 dibles ; active. Inhabits and feeds on decayed 

 wood. Pupa isomorphous. Imago with monili- 

 form antennae ; corneous, masticatory mandibles ; 

 large porrected head ; elongate prothorax ; wings 

 uniformly and fully developed, recumbent, de- 

 flexed, not folded, beautifully reticulated ; tarsi 

 four-jointed ; telum with a seta : flight diurnal, in 

 the sunshine. Raphidia. 



807. Lace-winged-flies {Hemerobiites). Larva, 

 with filiform antennae ; prominent, corneous man- 

 dibles and maxillae ; sacciferous, carnivorous. 

 Inhabits the leaves of vegetables. Pupa necro- 

 morphous ; changes within the sack formed by the 

 larva. Imago with long, moniliform antennae ; 

 corneous, masticatory mandibles, wings fully 

 and equally developed, not folded, beautifully 



