134 MANDIBULATxV. NEUROPTERA. 



He.lutarius. Linne? — Shaw, G. Z. v.\'i. pi. 83. Jig. i-nf'. — Si. lutarius. Steph. 



Catal. 314. No. 3533. 

 Dull, deep black : wings fuscous, with black nervures. 

 The female lays a great quantity of brown conical eggs, on the leaves of 



aquatic plants, &c.: they are dispersed with great symmetry, and form 



large plates : the larva are very active, and swim well. 



Very abundant in the vicinity of London, especially on the banks 

 of the Thames, in Battersea-fields, near Putney, Hammersmith, &c. : 

 found also near Ripley and Hertford, in the north of England and 

 Scotland ; also in Devonshire, near 13over, &c. 



Family II.— PERLIDJE, Leach. 



AntenncE remote, inserted before the eyes, setaceous, nearly as long as the body, 

 consisting of very numerous short articulations, the basal one being largest : 

 mandibles distinct : palpi exerted, inflexed, filiform or setaceous, maxillary 

 longest, the former five-jointed : head as broad as, or broader than, the 

 collar, somewhat trigonate, obtuse in front : eyes prominent, rather globose : 

 ocelli three, placed in a triangle : collar flat, transverse-quadrate : wings 

 incumbent, posterior generally largest, with longitudinal folds on their inner 

 margin, nervose, twice as long as the abdomen, which is soft, depressed- 

 cylindric, elongate, often furnished at the apex with two many-jointed setae 

 at the apex : legs compressed : tibia; and tarsi elongate-cylindric, the latter 

 three-jointed, short, the terminal joint longest and obconic. 



The insects included in this family have the wings incumbent during 

 repose, but like those of the two foregoing families the reticulations 

 frequently vary in the same specimen : the head is large ; ocelli three 

 in number, the abdomen frequently furnished with two articulate 

 setae, and the tarsi are always simple : the insects frequent damp and 

 marshy places. The indigenous species may be thus divided into 

 genera : — 



Cauda setis 2-bus multiarticulatis instructa. 

 Abdomen validum. 



^/« in utroque sexu consimiles : . . 27- Isogekus. 



dissimiles : . .26. Perla. 



siibgracile : . . . . . 28. Chloroperla. 



nmtica. 



Antennis gracilibus, articulis subindistinctis : . 29. Nemoura. 



validioribus, articulis submoniliformibus : 30. Leuctra. 



