ACADEMY OF NATURAL SCIENCES. 359 



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Mr. Nystroni presented a paper on the origin of the Table Moun- 

 tain in Tuolumne and Calaveras counties. 



Regular Meeting, June 17th, 1867. 

 Vice President Ransom in the Chair. 



Twenty members present. 



Donation to the Cabinet : Specimens obtained in excavating on 

 the Beideman tract, by G. Yale. 



Mr. Gabb presented a communication on the " Geology of Lower 

 California," which was referred to the Publication Committee, and 

 ordered printed as one of the Memoirs of the Academy. 



Mr. Gabb also communicated the following translation of part of 

 a letter received by him from Sr. Don Antonio Raimondi, of Lima, 

 Peru, with reference to some geological features of that country : 



I have just received a letter from Professor Eaimondi, accompanying a»very 

 interesting collection of fossils, sent through my lamented friend Mr. Pemond, 

 but which I have not yet received. After remarking that he had not time to 

 write a detailed account of the country to assist me in my determinations of 

 the geological ages, he gives the following condensed but interesting descrip- 

 tion of the country, which I have considered of sufficient value to warrant its 

 immediate publication. I translate this portion of the letter in full. 



" Peru, or at least the great chain of the Cordillera which divides the whole 

 of America into two parts, comprises various smaller chains, often very high, 

 and here consisting of four, nearly parallel. The principal of these are two, one 

 of which is the dividing line between the waters emptying into the Pacific on 

 one side, and the tributaries of the Amazon on the other. This is what is 

 properly called the Cordillera of the Andes, or the Western Cordillera. The 

 other chain is called the Eastern Cordillera, and in some points is as elevated 

 or even surpasses in height the true Cordillera. In the southern part of Peru, 

 for example, it is entirely covered with perpetual suow, and contains very 

 elevated peaks, including, in that part which is prolonged into Bolivia, the two 

 colossi called Sorata or Illampu and Illimani. The Eastern Cordillera is 

 of the greater geological age, appearing to be entirely composed of micaceous 

 and talcose schists which have been metamorphosed by the elevation of the 

 granites, those which have also introduced into these schists numerous veins of 

 quartz, which in some places are quite rich in gold. This elevated chain has 

 been cut very deeply by numerous rivers, which, taking their origin in the 



