EXPLANATION OF PLATE 34 



Fig. A. Monterey chert, Telegraph Canon, east of Berkeley. Shows wedg- 

 ing out of small chert beds. Shows the manner in which laminations of chert 

 abut upon the bounding surfaces of the beds. 



Fig. B. Banded chert from Monterey, showing alternations of black flinty 

 chert with white shale. (Two-thirds natural size.) 



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