CHAP. XII. 



Conception. 



399 



tion in this neighbourhood is generally horizontal; but 

 near Lirguen the beds dip NW. at an angle of 23° ; 

 near Concepcion they are also inclined : at the northern 

 end of Quinquina they have been tilted at an angle of 

 30° and at the southern end at angles varying from 15° 

 to 40° : these dislocations must have taken place under 

 the sea. 



A collection of shells, from the island of Quiriquina, 

 has been described by M. d'Orbigny : they are all extinct, 

 and from their generic character, M. d'Orbigny inferred 

 that they were of tertiary origin : they consist of : — 



1. Scalaria Chilensis, d'Orbig. 



1 Voyage, Part. PaL' 



2. Natica Araucana, do. 



3. Natica australis, do. 



4. Fusus difficilis, do. 



5. Pyrula longirostra, do. 



6. Pleurotoma Araucana, do. 



7. Cardium auca, do. 



8. Cardium acuticostatum. 



d'Orbig. ' Voyages, Pal.' 



9. Venus auca, do. 



10. Mactra cecileana, do. 



11. Mactra Araucana, do. 



12. Area Araucana, do. 



13. Nucula Largillierti, do. 



14. Trigonia Hanetiana, do. 



During a second visit of the Beagle to Concepcion, 

 Mr. Kent collected for me some silicified wood and 

 shells out of the concretions in the sandstone from Tome, 

 situated a short distance north of Lirguen ; they consist 

 of:— 



1. Natica australis, d'Orbig. 



' Voyage, Pal.' 



2. Mactra Araucana, do. 



3. Trigonia Hanetiana, do. 



4. Pecten, fragments of, pro- 



bably two species, but too 



imperfect for description. 



5. Baculites vagina, E. Forbes, 



PL V. f. 3. 



6. Nautilus d'Orbignyanus, E. 



Forbes, PL V. f . 1 (a) and 

 1(b). 



Besides these shells, Captain Belcher l found here an 

 Ammonite, nearly three feet in diameter, and so heavy 

 that he could not bring it away ; fragments are deposited 

 at Haslar Hospital : he also found the silicified vertebras 

 of some very large animal. From the identity in 



1 * Zoology of Capt. Belcher's Voyage,' p. 1G3. 



