Plaie XIII. 



Fig. 1 a b. Trapezium ventricosum Yok. Left valve. Otake. P. 108. 



Fig. 2. Cardium braunsi Tok. Right valve. Otake. P. 155. 



Fig. 3. Diplodonta nsta Gld. Left valve. Otake. P. 159. 



Fig. 4. Venericardia cipangoana Yok. Left valve. Otake. P. 162. 



Fig. 5. Cliama semipnrpnrata Lke. Convex valve. Otake. P. 161. 



Figs. 6, 7. Venericardia toneana Yok. 6. Left valve. 7. Right valve. Shitô. 



Enlarged about 4 times. P. 163. 

 Fig. 8. Crassatella nana Ad. et Rve. Right valve. Kioroshi. P. 164. 

 Figs. 9, 10. Montacuta oblongata Yok. 9. Left valve. 10. Right valve. Drawn 



after Oji specimens, those from Kazusa and Shimosa being too imperfect 



for figuring. P. 157. 

 Fig. 11. Trichotropis unicarinata Brod. Shito. P. 75. 

 Figs. 12, 13. Terebra tsuboiana Yok. 12. Kioroshi. 13. A living shell from 



Sagami Sea for comparison, the sculpture being more distinct. P. 35. 

 Figs. 14, 15. Corbicula sandaiformis Yok. 14. Left valve. 15. Right valve. Shito. 



P. 165. 

 Fig. 16. Trapezium liratum Reeve. Left valve. Otake. P. 168. 

 Fig. 17. Trapezium nipponicum Yok. Right valve. Otake. P. 167. The left 



valves shown in figs. 12 and 18 of plate VI may be the young forms of 



this species. 

 Figs. 18, 19. Corbicula kobelti Yok. 18. Right valve. 19. Left valve. Shito. P. 



166. 



