36 [APPENDIX 



formation, the fossils remain very entire and no change in structure is 

 observable, except where the trachitic masses have broken through both. 



Among the hills south of Monterey, other evidences of recent eleva 

 tion from the intrusion of recent igneous rocks are found ; and these 

 occur among that group of sedimentary formations which have been 

 denominated as the post ' Pliocene ; (see Table,) these are found on the 

 Carmello Creek, three miles above Meadow's Ranch, where the fine 

 grained sandstone, containing impressions of existing Crustacea are found 

 resting upon the granite, but tilted from their former horizontal position 

 by intrusion of recent trap rocks from beneath. This same feature is 

 noticeable north of Montere}^, and into the Santa Cruz Mountains, where 

 the marine formations of the Pliocene period are found elevated to dif 

 ferent heights above the sea, for miles interior from the present coast 

 line. With these facts before us, it will be impossible to arrive at any 

 other conclusion than that the volcanic series of which we have been 

 speaking, has been continued into a period comparatively recent, arid 

 was the active agent in producing those disturbances so manifest through- 

 throughout those portions of these mountains under our consideration. 



An interesting feature in the geology of the eastern part of the 

 Monte Diablo range has been developed during the past season, by the 

 officers of the United States Land Survey, which is worthy of note, as 

 illustrating the mutations which have been going on in different parts of 

 the country, and has served also to fix the age of districts hundreds of 

 miles remote from each other ; the marine shells brought into the Sur 

 vey office by Mr. Yon Schmidtz, f.-orn the hills bordering the west side 

 of the Tulare Lake are fpund to be indentical with those obtained from 

 the Buttes on the Sacramento Valley ; among the fossils are found the 

 Area, of which there are three species, with two species of Cardium, 

 differing from any found in our waters at the present time. 



The surveys of the United States Bail Road Exploring Expedition, 

 under command -of Lieutenant Stoneman and Williamson, on the desert 

 of the Colorado has been the means of eliciting much valuable informa 

 tion of that almost unknown and desert waste. The personal and atten 

 tive examinations of Mr. W. P. Blake, geologist of the exploring party 

 has opened a new field for investigation in addition to those already- 

 existing in other parts of the State. The old water line of the Gulf of 

 California has been traced with unerring certainty for a long distance 

 into the interior, and the fossil remains of marine animals and shells are 

 found promiscuously mingled with those of fresh-water origin, which 

 subsequently occupied the place where the waters of the Pacinc formerly 

 held undisputed sway. The discovery and demonstrations of those in 

 teresting changes in the elevation of the interior of this part of the 

 State above the level of the sea, with its recession from natural 

 causes, reflects much credit on the discrimination, and careful judg 

 ment of Mr. Blake, and must be regarded as a great acquisition to 

 our very limited stock of knowledge respecting the absolute condi 

 tion of that extensive portion of the interior. Among all those who 

 have preceded him in crossing this "Jornada" at different points, 

 not a word of information has been elicited from which not even a pro 

 bability of its true condition could be gleaned ; until the present time it 

 was* a blank in the geological history of this part qf our continent ; how 



