Geological Observations on South America

by Charles Darwin

3. Pecten purpuratus, Lam.

4. Chama, probably echinulata, Brod.

5. Calyptraea Byronensis, Gray.

6. Calyptraea radians (Trochus, Lam.)

7. Fissurella affinis, Gray.

8. Fissurella biradiata, Trembly.

9. Purpura chocolatta, Duclos.

10. Purpura Peruviana, Gray.

11. Purpura labiata, Gray.

12. Purpura buxea (Murex, Brod.).