CHAP. IX. 



Elevation of Lima. 



267 



common salt. I collected eighteen species of shells of 

 all ages and sizes. Several of the univalves had evi- 

 dently long lain dead at the bottom of the sea, for 

 their insides were incrusted with Balani and Serpulse. 

 All, according to Mr. G. B. Sowerby, are recent species : 

 they consist of — 



1. Mytilus Magellanicus : same as 



that found at Valparaiso, and 

 there stated to be probably 

 distinct from the true M. 

 Magellanicus of the east 

 coast. 



2. Venus costellata, Sowb. 'Zool. 



Proa' 



3. Pecten purpuratus, Lam. 



4. Chama, probably echinulata, 



Brod. 



5. Calyptrasa Byronensis, Gray. 



6. radians (Trochus, 



Lam.). 



7. Fissurella affinis, Gray. 



8. biradiata, Trembly. 



9. Purpura chocolatta, Duclos. 



10. Peruviana, Gray. 



1 1. labiata, Gray. 



12. buxea(Murex,Brod.). 



13. Conch olepas Peruviana. 



14. Nassa, related to reticulata. 



15. Triton rudis, Brod. 



16. Trochus, not yet described, 

 but well known and very 

 common. 



17 and 18. Balanus, two species, 

 both common on the coast. 



These upraised shells appear to be nearly in the 

 same proportional numbers — with the exception of 

 the Crepidulae being more numerous — with those on 

 the existing beach. The state of preservation of the 

 different species differed much ; but most of them were 

 much corroded, brittle, and bleached : the upper and 

 lower surfaces of the Concholepas had generally quite 

 scaled off: some of the Trochi and Fissurellae still 

 partially retain their colours. It is remarkable that 

 these shells, taken all together, have fully as ancient an 

 appearance, although the extremely arid climate appears 

 highly favourable for their preservation, as those from 

 1,300 feet at Valparaiso, and certainly a more ancient ap- 

 pearance than those from 500 to 600 feet from Valparaiso 

 and Concepcion : at which places I have seen grass and 

 other vegetables actually growing out of the shells. 

 Many of the univalves here at San Lorenzo were filled 

 and united together by pure salt, probably left by the 



