74 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser. 



2. The One Hundred-Fathom Plateau 100 



3. The San Pablo Submerged Valley 100 



4. The Todos Santos Submerged Valleys loi 



5. The Submerged Valley of Descanso Bay 102 



6. The Submerged Valley of Los Coronados Islands . . 102 



I. The Extent and Direction of the 

 Coast North of Latitude 32° 32'. 



The general direction of the Pacific Coast of the United 

 States from San Diego to the Strait of Fuca is as follows : 



From San Diego, in latitude 32° 32', longitude 117° 08', 

 to Point Arguello at the western entrance to the Santa 

 Barbara Channel, in latitude 34° 34', longitude 120° 38', the 

 coast runs nearly northwest by west for 225 miles; and off 

 the northern part of this stretch lie the mountainous Santa 

 Barbara islands. From Point Arguello to Cape Mendocino, 

 in latitude 40° 26', longitude 124° 22', it runs northwest by 

 north for 525 miles, and this stretch includes Monterey 

 Bay, the Gulf of the Farallones, and Bodega Bay. From 

 Cape Mendocino to Cape Flattery, in latitude 48° 23', 

 longitude 124° 44', it runs north for 480 miles and is broken 

 by the Columbia River and smaller rivers. 



I. San Diego to Santa Cruz. 



In the region of San Diego, south and north, there are 

 general depressions in the Coast Range of mountains; and 

 the immediate seaboard is a terrace of 100 to 200 feet eleva- 

 tion, with hills rising to 1,000 feet in ten miles. The great 

 plains of Los Angeles are thirty miles broad, and the Santa 

 Clara River comes through a flat valley from ten to fifteen 

 miles broad. 



Abreast the Santa Barbara Channel the main shore is 

 formed by the southern face of the high, abrupt range of 

 Santa Ynez, which reaches 3,823 feet elevation in four 

 and a half miles from the sea, and runs east and west. The 

 Santa Monica is a parallel range a little to the south, ending 



