82 CALIFORN'/A ACADEMY OF SCIENCES. [Proc. 30 Ser. 



the small cove, and carries 25 fathoms to within 150 yards 

 of the three-fathom line. From its head it stretches three 

 miles N. 40° W., to the 225-fathom curve, and then 2^ 

 miles N. 70° W., to the 300-fathom curve, beyond which 

 there are no immediate soundings. The valley is quite 

 narrow out to the 200-fathom curve. 



On the south side of the valley the 500-fathom line lies 

 three miles broad off Point La Jolla, and thence the sound- 

 ings deepen rapidly seaward, but to the southward the 50 

 fathom plateau increases in breadth to five miles off False 

 Bay. North of the valley the 500-fathom line is barely two 

 miles off shore and parallel therewith for 17 miles; outside 

 this narrow plateau the water deepens rapidly to 200 

 fathoms. The greatest observed depth is 297 fathoms at 

 5^ miles from the beach, and about where the normal 120 

 fathom line would pass. Unfortunately the soundings are 

 not numerous enough to afford much more information. 



The fine dark gray sand of the bottom extends outward 

 to about 25 fathoms. There is green mud and fine sand, 

 with added broken shells, on the NE. and SW. slopes of the 

 valley in 100 fathoms; at 150 fathoms, green mud alone. 

 Approaching the head in 115 fathoms there is green mud 

 and fine sand; and at the head in 25 fathoms hard bottom, 

 which may be sand or rock. 



The geographical position of the head of the valley at 

 the 25-fathom curve is: 



Latitude 32° 51 14;' N.; longitude 117° 16' W. 



2. The Carlsbad Submerged Valley. 



One mile south of the town of Carlsbad the 50-fathom 

 plateau is sharpl}^ indented by a broad valley 125 fathoms 

 deep on that line. The 50-fathom curve is carried into the 

 normal 25-fathom line; but at 200 fathoms the signs of a 

 valley disappear. The geographical position is: 

 Latitude 33° 07^' N., longitude 117° 21%' W, 

 The character of the country inside of the sea-coast 

 plateau is irregularly rolling and reaches 2,000 feet elevation 



