PERLIDJE. — LEUCTRA. 145 



A. Antenna somewhat moniliform, each joint producing a whorl of hairs on 

 both sides : head broad, depressed. 



Sp. 1. geniculata. Plate xxxi. f. 3. — Nigro-picea, capite rufo-piceo, nigra 

 itario, abdomine supra rufo-piceo, lateribus nigris, pedibus pallide brunneisj 

 Jemoribus posterioribus annulo nigro, antennis pallide rufis, pilosis. (Long, 

 corp. 3 — 3| lin. ; Exp. Alar. 9 — lOg lin.) 



Le. geniculata. Steph.Nomen. 2d edit. col. 118. — N. G. (548). geniculata. Sleph. 

 Catal. 316. No. 3561, 



Pitchy-black : head pitchy-red, with the eyes, ocelli, and some frontal marks 

 black ; collar with the sides straight, the disc rugose, and with three dorsal 

 channels ; mesothorax pitchy-red in front ; abdomen above pitchy-red, its 

 sides and beneath black ; legs pale brown, the four hinder femora with a 

 blackish ring near the apex; tips of the tibiae and of the tarsal joints 

 blackish; antennae pale pitchy-red, the articulations very distinct, each 

 producing a whorl of blackish hairs on each side; wings pale fuscous, with 

 darker nervures. 



Apparently rare : taken occasionally within the metropolitan 

 district in June ; also in the New Forest and in Scotland. 



B. AntenncE slender and pilose : head small. 



Sp. 2. fusciventris. Fusco-nigra, collaris lateribus rotundatis, ano piceo, pedibus 

 pallide rufo-piceis, tar sis nigris. (Long. corp. 2^ lin.; Exp. Alar. 7g lin.) 



Ne. fusciventris. Steph. Catal. 316. A^o. 3559. 



Brown-black : collar with a longitudinal and two nearly parallel dorsal 

 channels, the rest of the surface rugose ; abdomen fuscous, with the apex 

 pitchy ; legs pale pitchy-red, with blackish tarsi ; palpi and antennse black ; 

 wings fuscescent, with darker nervures, the edges of some of the costal 

 nervures fuscous. 



Found, in June, near Hertford : not common. 



Sp. 3. abdominalis. Piceo-nigra, collare quadraio, ore pedibusque pallide 

 ochraceo-rufis, tarsis nigricantibus, abdomine pallide rufo, maculis lateralibus 

 sirigaque ventrali piceo-nigris. (Long. corp. 3 lin. ; Exp. Alar. 8 — 9^ lin.) 



Ne. abdominalis. Steph. Catal. 316. No. 3560. 



Pitchy-black : mouth pale red ; collar nearly quadrate, its surface rugose, 

 with five longitudinal dorsal channels, the two outer ones, on each side, 

 placed obliquely ; abdomen pale red, with a row of black spots on each 

 side, and a broad streak of black beneath ; legs pale ochreous-red, the tips 

 of the hinder femora and the tarsi blackish ; wings fuscescent, the nervures 

 darker, with a fuscescent shade on each side, the apex of the costa the 

 same ; antenna? black. 



Also found occasionally at Hertford, in June and July. 

 Mandibulata, Vol. VI., August 15th, 1836. t 



