Figure 1. 
(Page 125.) 
Figure 2. 
(Page 125.) 
Figure 3. 
(Page 125.) 
Figure 4. 
(Page 125.) 
Figure 5. 
(Page 125.) 
Figure 6. 
(Page 126.) 
Figure 7. 
Figure 8. 
(Page 124.) 
Figure 9. 
(Page 120.) 
Plate XXIII 
Corbicula dowlingi n. sp. 
Right valve of holotype. Viet. Mem. Mus., Cat. No. 6191. Natural scale. 
Same specimen. Dorsal view. Note external ligament. Natural scale. 
Modiolus silentiensis n. sp. 
Right valve. Paratype. Yict. Mem. Mus., Cat. No. 6112. Natural scale. 
Right valve. Holotype. Yict., Mem. Mus., Cat. No. 6190. Natural scale. 
Rhytophorus? caurinus n. sp. 
Drawing, X 2. Holotype. Viet. Mem. Mus., Cat. No. 6192. Natural scale. 
Prionotropis caurinus n. sp. 
Side view. Holotype. Viet. Mem. Mus., Cat. No. 6193. Natural scale. 
Same specimen. Ventral view. Note keel. Natural scale. (Page 126.) 
Pecten silentiensis n: sp. 
Posterior view of holotype. See Plate XXII, figures 1, 2. Natural scale. 
Pinna dolosoniensis n. sp. 
Side view. Holotype. Viet. Mem. Mus., Cat. No. 6102. Natural scale. 
