316 THOMAS SAY FOUNDATION 



PLATE 13. 



Wings of Perla. 



Fig. 1. Perla ramosa, sp. nov. 



Fig. 2. Perla immarginata Say 



Fig. 3. Perla media Walk. 



Fig. 4. Perla sabulosa Bks. 



Fig. 5. Perla languida sp. nov. $ 



Fig. 6. Clioperla marmorata sp. nov. 



Fig. 7. Perla languida sp. nov. brachypterous $ 



Fig. 8. Perla capitata Pict. 



