150 Mr. E. MacLachlan's Monograph of 



I divide the Planipennia into tliree divisions^ Sialina, 

 Hemerobiina, and Panorpina. 



I. SIALINA. 



Wings in repose more or less vertically deflexed ; tlie 

 posterior pair with a slightly developed anal portion. 

 Front not prolonged into a rostrum. Larva aquatic, or 

 sub- cortical. 



II. HEMEROBIINA. 



Wings in repose very strongly vertically deflexed; 

 mostly similar in form; no anal space in the posterior, 

 which are thus scarcely folded. Front not prolonged 

 into a rostrum. Larva arboreal, or aquatic. 



III. PANORPINA. 



Wings in repose carried horizontally in a longitudinal 

 direction, linear, equal. * Front prolonged into a ros- 

 trum. Larva living in the earth. 



Division I. SIALINA. 



AntenncB filiform. Head transverse (Sialidce) or elon- 

 gate {Baphidiidce); front not prolonged ; mandibles tooth- 

 ed internally J maxillary 'palpi filiform, 5-jointed; labial 

 3-jointed. Protliorax moderate and thick [Sialidce), or 

 very long and slender {Baphidiida') . Abdomen robust. 

 Tai'si 5-jointed, the third {RapliidHda^) or fourth [Siali- 

 dce) joint cordate ; %ingues not serrated. | 



Wings ovate, sub-equal, the anal area in the posterior 

 pair slightly developed. Sub-costa joining the costa 

 before the apex [Baphidiidce) , or becoming confluent 

 with the radius [Sialidce); radius parallel with the sub- 

 costa, emitting two or more sectors; the longitudinal 

 veins and their branches are mostly furcate on the mar- 

 gins, are connected by few transverse nervules, thus 

 forming large areoles; pterostigma circumscribed [Ba- 

 phidiidce) or not [Sialidoi) . 



Larva aquatic, or su.b- cortical. 



The two families, Sialida-' and Baphidiidce, contain each 

 only one British genvis, and the particular characters of 

 each family are indicated in those above given for the 

 division. 



* In Boreus the wings are rudimentary. 



t In the large exotic Sialidce belonging to the genera Corydalis and 

 Chauliodes, the antennfe are often pectinated in the male, and the joints 

 of the tarsi are all filiform. 



