NEOCENE STRATIGRAPHY. 285, 



southeastward. The main peaks shown upon the sketch- 

 map and adjacent region. 



Pescadero Series. — This series makes up the hills of 

 northeastern San Francisco. The eastern side of the 

 San Bruno Mountains and hills northwest of Ocean View.. 

 At Point San Pedro. Eastern foothills, from Redwood- 

 Searsville road to south of Mayfield. Main ridge, from 

 San Mateo-Spanish Town road to headwaters of Pesca- 

 dero Creek. Pescadero Point to Pigeon Point. 



Monterey Series. — Western flank of main ridge, from 

 near Spanish Town, southeastward. Coast, from Point 

 New Year to Santa Cruz. 



Merced Series. — Lake Merced to Mussel Rock on the 

 coast, and extending southeast to Milbrae, forming foot- 

 hills. Foothills near Stanford University and Mayfield. 

 Foot of main ridge, west side of Coal Mine Canon. Coast, 

 from Point Montara to Pescadero Creek. At Point New 

 Year. Santa Cruz to south of Capitola. 



Pleistocene and Recent. — Most of San Francisco. 

 Valley of Lake Merced. Between foothills and Bay of 

 San Francisco. Santa Clara Valley. Small areas in 

 foothills and in stream valleys. Mussel Rock to Point 

 San Pedro. Raised beaches on coast, from Point Mon- 

 tara to Pajaro River. Valley of Pajaro River. 



S tratigraphtcal delations of the Formations. — There 

 are three, and probably four, marked periods during each 

 of which sedimentation was more or less continuous, each 

 being followed by upheaval and folding, and each being 

 laid down unconformably upon the preceding. The 

 formations belonging to the first of these have been grouped 

 together and have been called for want of a better name, 



The Metamorphics of the Coast Ranges. — These in- 

 clude the Gavilan limestone, the phthanite or radiolarian 

 chert and the metamorphic sandstone. Little is known 

 accurately of these formations. The phthanite and meta- 



