PLATE XXXIII 



PAGE 



Figs. 1-3. GRYPH^A (PYCNODOXTE) VESICULARIS (Lamarck) Race E 576 



1. Exterior of left valve. 



2. Interior of same. 



3. Interior of right valve. 



Manasquan formation, Noxontown Mill Pond, Delaware. 



Figs. 4-6. GRYPH.EA (PYCNODOXTE) PUSILLA Gardner n. sp 578 



4. Exterior of left valve. 



5. Interior of same. 



6. Interior of right valve. 



Monmouth formation, Great Bohemia Creek, Cecil County. 



