chap. ix. Elevation of Coqtiimbo. 



2 5l 



1. Calyptraea radians. 



2. Turritella cingulata. 



3. Oliva Peruviana. 



4. Murex labiosus, var. 



5. Nassa (identical with a living 

 species). 



6. Solen Dombeiana. 



7. Pecten purpuratus. 



8. Venus Chilensis. 



9. Amphidesma rugulosum. The 

 small irregular wrinkles of the 

 posterior part of this shell are 

 rather stronger than in the 

 recent specimens of this species 

 from Coquimbo. (Gr. B. 

 Sowerbv.) 



10. Balanus (identical with liv- 

 ing species). 



On the syenitic ridge, which forms the southern 

 boundary of Herradura Bay and Plain, I found the 

 Concholepas and Turritella cingulata (mostly in frag- 

 ments), at the height of 242 feet above the sea. I could 

 not have told that these shells had not formerly been 

 brought up by man, if I had not found one very small 

 mass of them cemented together in a friable calcareous 

 tuff. I mention this fact more particularly, because I 

 carefully looked, in many apparently favourable spots 

 at lesser heights on the side of this ridge, and could not 

 find even the smallest fragment of a shell. This is only 

 one instance out of many, proving that the absence of 

 sea-shells on the surface, though in many respects inex- 

 plicable, is an argument of very little weight in opposi- 

 tion to other evidence on the recent elevation of the 

 land. The highest point in this neighbourhood at which 

 I found upraised shells of existing species was on an 

 inland calcareous plain, at the height of 252 feet above 

 the sea. 



It would appear from Mr. Caldcleugh's researches, 1 

 that a rise has taken place here within the last century 

 and a half; and as no sudden change of level has been 

 observed during the not very severe earthquakes, which 

 have occasionally occurred here, the rising has probably 

 been slow, like that now, or quite lately, in progress at 

 Chiloe and at Valparaiso : there are three well-known 

 rocks, called the Pelicans, which in 1710, according to 



1 ' Proceedings of the Geological Society,' vol. ii. p. 446. 

 12 



