sj cs *-" 



/S 



;3 



MEMOIRS 



PUESENTED TO THE 



CALIFORNIA ACADEMY OF SCIENCES. 



VOL. I, PAUL II. 





THE NATURAL SYSTEM OF 



VOLCANIC ROCKS 



RICHTHOFEN. 



S A N F RANCIS C O : 



TOWNE A-ND BACON, PRINTERS. 



L868. 





