4-io 



Tertiary Formations : 



PART II. 



secondary forms. Hence I conceive there can be no 

 doubt that these formations are tertiary. — a point ne- 

 cessary to consider, after the case of Concepcion. The 

 fifty-nine species belong to thirty-two genera ; of these, 

 Gastridium is extinct, and three or four of the genera 

 (viz. Panopsea, Rostellaria, Corbis ?, and I believe 

 Solecurtus) are not now found on the west coast of South 

 America. Fifteen of the genera have on this coast 

 living representatives in about the same latitudes with 

 the fossil species; but twelve genera now range very 

 differently to what they formerly did. The idea of the 



Genera, with living and 



Latitudes, in which found 



Southernmost latitude, in 1 



tertiarv species on the 



fossil on the coasts of 



which found living on the 



west coast of S. America ] 



Chile and Peru 



west; coast of S. America 



Bulla . 



30° to 43° 30' 



12° near Lima 



Cassis . . . 



34° 



1°37' 



Pyrala . . 



34° (and 36° 30' at 



Concepcion) 



5° Payta 



Fusus . . . 



30° to 43° 30' 



23° Mexillones ; re- 

 appears at the St. 

 of Magellan 



Pleurotoma . 



34° to 43° 30' 



2° 18' St. Elena 



Terebra . . . 



34° 



5° Payta 



Sigaretus 



34° to 44° 30' 



12° Lima 



Anomia . . . 



30° 



7° 48' 



Perna . 



30° 



1° 23' Xixappa 



Cardium . . . 



£0^ to 34° (and 36° 

 30' at Concepcion) 



5° Payta 



Artemis . . 



30° 



5° Pavta 



Voluta . . . 



34° to 44° 30' 



Mr. Cuming does 

 not know of any 

 species living on 

 the west coast, 

 between the equa- 

 tor and lat, 43° 

 south; from this 

 latitude a species 

 is found as far 

 south as Tierra 

 del Fuego. 



1 M. d'Orbigny states that the genus Natica is not found on the 

 coast of Chile ; but Mr. Cuming found it. at Valparaiso. Scalaria 

 was found at Valparaiso ; Area, at Iquique, in lat. 20°, by Mr. 

 Cuming ; Area, also, was found by Capt. King, at Juan Fernandez, 

 in lat. 33° 30'. 



