37 



the stratum being about 3 feet thick on the southern border and increasing iu thickness as the 

 channel is approached. Where it could be ascertained the substratum was found to be bard, and 

 is, probably, of saud, as the bottom contiguous is of that description. It is probable that narrow 

 ledges of oysters exist on both sides of the Beep Creek Channel, above Beach Island, but lack of 

 time prevented our verifying the supposition. The bed is unbroken, and the oysters single and 

 presenting the same general characteristics as on the beds already described. A moderate number 

 of young was found, and the presence and destructive effects of the drills were noticed. 



Parker's Bed. — This is a small bed lying east of Watts' Island, and on the weslern side of the 

 channel into Pocomoke Sound. It is long and narrow, extends north and south five-eighths of a 

 mile, and has an average width of one-fifth of a mile. The depth of water is from 12 to 24 feet, 

 the shoal water being found about the middle of the bed and the deepest water on the southeastern 

 portion. The bed is unbroken except about the edges, and the oysters are spread uniformly over 

 the area, which comprises 495,000 square yards. The bottom is hard and consists of a stratum, 3 

 feet thick, of shells and mud, over a stratum of hard sand or clay. The contiguous bottoms are 

 of soft sand or mud, with a hard substratum. The oysters were single, of moderate size, and 

 similar in quality to those on the other beds of the Sound. They were not numerous, the number 

 to the square yard being 0.57, but that number is larger than on any of the other beds in Poco- 

 moke. Some of the red sponge was fouud, but nothing else. Large numbers of young and drills 

 (astyris) were discovered, but for some reason the drills appeared to have been less destructive 

 than elsewhere. Those oysters fouud near the bed were larger than those on it, but had no young 

 attached to them. 



The Brig Bed. — This bed lies to the northward and westward and off the mouth of Chescon- 

 nessex Creek. It is small, nearly oval in shape, and comprises an area of 517,000 square yards. 

 Its extent east and west is five-eighths of a mile and its greatest width, north and south, is three- 

 tenths of a mile. The depth of water is from 19 feet on the eastern edge to 48 feet on the western. 

 The bed is unbroken, except about the edges, where the oysters are somewhat scattered; on the 

 solid portions they are not very evenly distributed, being more numerous about the center of the 

 bed than elsewhere. The bottom is hard, and probably of sand and shells, but, owing to the depth 

 of water, it was impossible to use the probe successfully; the contiguous bottoms are, however, of 

 the character described, and it is probable that there is no difference on the bed. The oysters 

 were large and single and of superior quality to any on the other beds. A moderate number of 

 young and a few drills were fouud, but no sponge or grass, though some of the latter was discov- 

 ered among the scattered oysters. The number to the square yard was 0.27. 



DENSITIES. 



The density of the water on the different beds was obtained in the same manner as in Tangier 

 Sound. 



The least density found, that of 1.0L13, was across the mouth of the Pocomoke Eiver at low 

 water of the spring tide. The water of the greatest density, that of 1.0174, was taken from about 

 the middle of the Sound, over the Bird, Buoy Spit, Muddy Marsh, and Hern Island Rocks. The 

 density over the beds, therefore, would be within those limits, the variation amounting to 0.0061. 



The effect of the tide does not appear to be invariable, as the greater densities were found as 

 frequently on the ebb tide as on the Hood. The depth of water and the prevailing winds have 

 probably a greater effect than anything else, as the density increases with the depth, and the 

 prevalence of easterly or southeasterly winds, backing the waters of the bay up into the Sound, 

 would have a like effect. As the variation noticeable during the space of eleven days, under 

 various conditions of weather, was so small, it can hardly be much greater at any time, and unless 

 much greater than showu by the records, and if representing the change in saliuitj r , it can have 

 but very little, if any, effect upon the oysters on the beds. By the following tables of comparison 

 it will be seen that the fluctuation of density is, as in Tangier Sound, greatest at the head of the 

 Sound and least at its entrance, with an increased fluctuation where the influence of the Mesongo 

 and Guilford Creeks is felt. 



On the beds above the Bird Rock the difference of density noticed was 0.0061. On the 

 remainder of the beds the difference was 0.0015, showing that there is a much smaller change in 

 the density over the southern beds than over the northern. 



