8o CALIFORNIA ACADEMY OF SCIENCES. [PROC. 3D Ser. 



2,000 fathoms at 70 miles W. SW. from Pigeon Point. 



It is curious that the Vitula shoal, upon which several 

 vessels reported only five or six fathoms, was located near 

 where this 2,000 fathoms depth was found. 



2,000 fathoms at 50 miles W. SW. from Southeast 

 Farrallon. 



1,726 fathoms at 29 miles directly W. from Southeast 

 Farallon. 



And continuing northward we have: 



2,000 fa.homs at 54 miles directly W. from Fort Ross. 

 2,000 " " 71 " " " " Point Arena. 



2,000 " "75 " W. SW. from Cape Mendocino. 

 1,700 " "50 " W. from Trinidad Head (41° 03'). 



A few soundings off and northwest from Cape Mendocino 

 indicate a submarine prolongation of this range of mountains. 



IV. The Submerged Valleys of the 

 California Coast. 



The first discovery of a distinct valley in the submerged 

 surface of the earth bordering the coast of California was 

 made in 1855 by the U. S. Coast Survey. It is known 

 as the Hueneme Submerged Valley. But as the operations 

 of the Coast Survey did not contemplate the development 

 of such physical characteristics, nothing further was done 

 in subsequent surveys or studies. Later discoveries resulted 

 merely from the hydrography necessary for navigation ; but 

 as the Santa Clara Valley opens directly upon the sea at 

 the spreading of its fifteen mile low, flat debouchment 

 between high mountains, it was thought that similar sub- 

 merged valleys might be discovered off San Diego, San 

 Pedro, Santa Monica, Monterey, and the Golden Gate. 

 Certainly none were expected off Point Dume, Carmel 

 Bay, and the high, compact mountains south of Cape 



Mendocino. 



All the submerged valleys so far developed lie south of 



