perlides. 147 



19. Perla arenosa. 



Perlii arenosa, Pictet, Hist. Nat. Neur. Perl. 178, II, pi. 10, f. 1. -J. 

 North America. 



20. Pkula Pennsvlvanica. 

 Perl;i Pemisylvanica, Riunb. Ilist. Nut. Ins. Neur. 456, 13. 



l^hil;i<k'li.liiu. 



21. Perla aunormis. 



Fiisca, fere cuneolor ; ahr fusce.scentes, siiperne apicibus reticu- 

 latic. 



Perla abiionnis, Newm. Ent. Mag. v. 177. Pivtct., Hist. Nat. New. 

 Perl. 180, 12. 



//. Trenton Falls. Presented bv the Entomoloijical Club. 



Group 4. PERLA. 



Alae apud stigma non maculatae. Vena subcostalis accessoria 

 simplex, aut reijulariter unilurcata vel bifurcata. Areola marginalis 

 apicalis venis duabus aut pluribus transversis. 



Perla, Pictet, Hist. Nat. Neur. Perl. 144, 4. 



Terminal part of the submar<^inal refjfion without cross veins ; 

 accessorj- vein of the subcostal vein without ramifications, or with 

 one or two refjular bifurcations ; marginal terminal areolet with at 

 least two transverse veins. Species of a large or middle si/e. of .i 

 more or less deep brown or yellowish colour. 



Sub-group 1. 



Species plus minusve obscure fuscap, magna; vel mediocre.s. 

 Prothorax lateribus reciis angulisquc acutis. Ahe subfuscrr vel 

 subfulvae, venis robust is. 



Species of lar<ie or moderate size: prothorax with straight 

 sides and .sharp angles : wiuirs with a brown or a tawny tinge, 

 strongly veined : general colour more or less deep brown. 



o 2 



