164 PERLIDES. 



Sub-genus 5. CHLOROPERLA. 



Alarum areola marginalis terminalis vena una aut nulla trans- 

 versa. Regio submarginalis venis transversis nullis apud apicem. 

 Venae subcostalis venula accessoria simplex aut bifurca, singula vel 

 duplici. 



Chloroperla p., Newman, Ent. Mag. v. 500. Steph. 111. Brit. Ent. 

 Mand. vi. 137. Pictet, Hist. Nat. Neur. 145, 5. 



Terminal part of the submavginal region without cross veins ; 

 accessory vein of the subcostal vein simple or bifurcate ; marginal 

 terminal areolet with at most one cross vein beyond that which ter- 

 minates the accessory vein at the costal vein. Species generally 

 small ; European species more or less yellowish green ; some exotic 

 species brown or blackish. 



Div. 1. 



Alae unicolores. 



Subdiv. 1. 

 Corpus plerumque nigrum. 



Sect. 1. 

 Caput et prothorax vitta dorsali flava. 



77. PEELA GUEEINII. 



Perla Guerinii, Pictet, Hist. Nat. Neur. Perl. 279, 55, pi. 30, f. 

 6-8. 



New Orleans. 



Sect. 2. 



Caput nigrum, flavo marginatum. Prothorax vitta media 

 nigra. 



78. PEELA MACULATA. 



Perla maculata, Pictet, Hist. Nat. Neur. Perl. 280, 56, pi. 30, f. 9. 

 Philadelphia. 



