PLATE XXIII. 



PAGE 



Figs. 1, 2. AcEOSTicHOPTEBis LONGiPENNis Fontaine 223 



1. Federal Hill, Maryland (after Fontaine). 



2. Hell Hole, Virginia (after Fontaine). 



Figs. 3, 4. RuFFORDiA GoEPPERTi (Dunker) Seward 231 



3. Fredericksburg, Virginia (after Fontaine). 



4. Pinna of same. X 3. 



Figs. 5, 6. RuFFOKDiA ACRODENTATA (Fontaine) Berry 230 



5. Dutch Gap, Virginia (after Fontaine). 



6. Pinna of same. X 2. 



522 



