260 



PATAGONIAN EXPEDITIONS : PALEONTOLOGY. 



GENERAL CONSIDERATIONS. 



THE PATAGONIAN BEDS. 

 HISTORY OF OUR KNOWLEDGE OF THE PATAGONIAN FAUNA. 



The first species of Invertebrates described from what is now known 

 under the designation " Patagonian beds" is: Hypechinus patagonensis 

 d'Orbigny (1842). Indeed, d } Orbigny has described, in the same publi- 

 cation, other species from Patagonia, but most of them came from the 

 northern parts of the country, and, as far as has been ascertained, do not 

 belong to the true Patagonian beds. 



Darwin mentions in 1846 from the Patagonian beds a large oyster 

 under the name of Ostrea patagonica, which is a mistake, this species be- 

 ing different (O. ingens}. In the same work, Sowerby (1846) gives de- 

 scriptions and figures of 24 species from Santa Cruz, San Julian, and 

 other localities, which undoubtedly belong to the Patagonian deposits. 

 They are the following (corrected names in brackets) : 



1 . Terebratula patagonica ( Terebractella /.). 



2. Nucula glabra (Leda g.). 



3. Nucula ornata (Malletia o.). 



4. Cucull&a alta. 



5. Trigonocaslia insolita (Limopsis *'.). 



6. Pccten geminatus. 



7. Pec ten c entrails. 



8. Crassatella lyelli (Crassatellites /.). 



9. Cardita patagonica. 

 i o. Cardium puelchum. 



1 1 . Venus meridionalis. 



12. Mactra (?) darwini. 



13. Mactra rugata. 



14. Trochus collar is (Gibbula Icevis). 



1 5 . Scalaria rugulosa. 



1 6. Crepidula gregaria. 



17. Natica solida (N. darwini). 



1 8. Turritella ambulacrum. 



1 9. Turritella patagonica. 



20. Struthiolaria ornata. 



21. Fusus noachinus (Siphonalia .). 



22. Fusus patagonicus (Trophon p^). 



23. Valuta alta ( ? ). 



24. Balanus variant. 



Including the large oyster mentioned by Darwin, these are 25 species, 

 of which 22 are represented in our collection, and belong undoubtedly to 

 the Patagonian beds. Of the remaining three, Leda glabra belongs here 

 according to v. Ihering; Mactra rugata is very doubtful, and, although 

 recorded from the typical locality at Santa Cruz, has never been found 



