PLATE 50. 
Page 
Fig. 1. Cypricardinia sublamellosa. 267 
1. The right valve, natural size. 
Fig. 2. Cypricardinia concentrica. 268 
2. The right valve of this species. 
Fig. 3. Cypricardinia crassa. 268 
3. The right valve, natural size. The posterior side is somewhat broken and obscure. 
Fig. 4. Megambonia lata. 277 
4. The left valve of this species. 
Fig. 5. Megambonia oblonga. 277 
5. The left valve of this species. 
Fig. 6. Megambonia cordiformis. 278 
6 a. Profile view from the anterior side of the shell. 
G b. View of the right valve, having the posterior cardinal extension abraded. 
Fig. 7. Megambonia ovata. 279 
7. The cast of the right valve. 
