PLATE XIII. 

 Pinna (continued). 



Figs. 



1. /'. Bobinaldina, d'Orb. Lower Greensand, Isle of Wight. Museum of 

 Practical Geology, No. 1263G. Ventral part of right valve. (P. DO.) 



2, 3. P. sp. Gault, Folkestone. 2. Sedgwick Museum; left valve. 3. Museum 

 of Practical Geology, No. 1 2641 ; portion of dorsal part of left valve, 

 X 6. (P. 99.) 



4-6. P. decussata , Goldf. Chalk. (P. 99.) 



4. Newtimber (Sussex). Brighton Museum, a, right valve; b, dorsal view of 



both valves ; c, dorsal part of right valve, X 3. 



5. Holaster planus zone, Balsham. Sedgwick Museum. Left valve. 



6. Trimiugham. Norwich Museum. Part of right \alve. 



