OYSTER BOTTOMS IN MATAGORDA BAY. 9 



it was possible to plot the position within a few yards. The biolo- 

 gist, following in a small boat, occupied these flag stations, system- 

 atically selecting at each, from soundings, a characteristic area. 

 Four steel-shod pikes were thrust into the bottom, marking out an 

 area 5 yards long and 1 yard wide, and everything on the bottom — 

 oysters, shells, and debris — was carefully tonged and examined. At 

 each such station the following data were taken : The number of oys- 

 ters under 1 inch in length, between 1 and 3 inches, and over 3 

 inches, respectively; the number or quantity of dead shells; the 

 shape, quality, and general condition of the oysters; and the species 

 of other animals and plants found. An examination of the entire 

 bed was then made in order to ascertain its general character, shape, 

 and approximate area, and the bottom was probed with steel-shod 

 lengths of iron pipe in order to ascertain the nature and depth of the 

 substratum. On the smaller beds one or two such examinations were 

 sufficient, but on the larger and more important ones a number of 

 stations were occupied. Full notes were made, and the result is a 

 complete and accurate record of the character of each bed at the time 

 of the survey in a form to be readily available for comparison with 

 future surveys, thus making possible a history of the beds showing 

 the effects of the fisheries and of the physical and biological vicissi- 

 tudes to which they may be in future subjected. 



The observations on the density and temperature of the water were 

 made by the sounding party at intervals of about 1 mile, in each case 

 the position of the boat being fixed by sextant observations. The 

 water was collected at a uniform distance of 14 inches above the bot- 

 tom by means of a stoppered bottle lashed to a pole, the cork being 

 withdrawn by a cord while the bottle rested on the bottom. A speci- 

 men of the water from each station was retained for examination as 

 to food value, while the density and temperature were noted at 

 once and entered in the sounding book. During the entire term of 

 the survey a series of tridaily observations of the density and temper- 

 ature of the water were made at the anchorage of the Fish Hawk. 

 These are useful for purposes of comparison and by illustrating 

 the rapid fluctuations due to meteorological conditions. 



The tide gauge was established at Matagorda, a geographically 

 central location, where observations were continued from January 

 20 to May 11, inclusive. A description of the tide gauge, bench mark, 

 and the plane of reference adopted will be given in the chapter treat- 

 ing of the tides. 



Upon arrival in Matagorda Bay, December 12, the Fish Hawk 

 anchored off Palacios, but soon after she was moved up to an anchor- 

 age about 4 miles below Dog Island Reef. Here she remained until 

 a few days before the conclusion of the survey, when she dropped 

 farther down the bay. As the upper part of the bay is much too shoal 



