DESCRIPTION OF CHART. 



The chart shows the character and location of the natural oyster beds and the barren 

 bottom. The oyster beds are included within solid orange lines and the density of the 

 growth of oysters over 3 inches long is indicated by the relative intensity of the shading. 

 In this classification the small oysters are disregarded and it therefore may happen 

 that a dense growth of oysters under 3 inches in length may occur in an area shown as 

 scattering. 



Barren bottom is imshaded, but its character as to consistency is indicated by 

 cncular symbols. Hard bottom is shown by solid black circles, ooze by circles with a 

 horizontal diameter, and intermediate consistencies by intermediate symbols. The 

 more open the circle, the softer is the bottom which it represents. Not all stations at 

 which the bottom was tested are shown, the purpose being to indicate the general 

 character and the transitions from one to the other. 



Depths are expressed in feet and refer to mean low water. 



The triangulation stations of the United States Coast and Geodetic Sum^ey, which 

 were determined with great acciu-acy and are permanently marked with concrete 

 monuments, are shown by triangles with an included circle. 



The subsidiary triangulation stations of the Bureau of Fisheries, less accurately 

 determined and marked by concrete monuments with an iron pipe in the center, are 

 shown by means of circles. The names of the stations are those used by the hydro- 

 graphic party and are usually abbreviations of the full name used by the Coast and 

 Geodetic Survey. 



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