66 



one. How much so it is impossible to say, but it is evident that a smaller number would indicate 

 a failure of the mature oysters. 



In calculating these numbers only first and second class oysters have been considered. 



It will be seen by the table that on all the beds above Hedge's Strait there has been a marked 

 decrease in the number of oysters to the square yard. That on the remaining beds, with the excep- 

 tion of Woman's Marsh and Johnson's beds, and considering the Thoroughfare beds as one, there 

 has been an increase in the number of oysters. That on all the beds in Pocomoke Sound there 

 has been a marked decrease. 



It will also be seen that on many of the beds the number falls below the standard of 0.4, that 

 on none of them is it very much greater, and that, generally speaking, the numbers are less than 

 the standard on those beds that show a gain upon the number established during 1878. 



It would appear, then, by one comparison, that most of the beds have not a sufficient number 

 of mature oysters upon them; and by the other, that however many were taken off, yet nature 

 could more than supply the demand. These inconsistent results may be the result of several 

 causes. The standard may be too high; but, as has been explained, if the beds are in equally good 

 condition, the probability is that the dredge would bring up a larger number from the old than 

 from the new beds. The smallness of the numbers on the lower beds may be due to the greater 

 depth of water and hardness of the bottom, though they do not differ greatly in that respect from 

 the beds in the bay, however much from those in the northern part of the Sound. 



It would not be wise to decide hastily, upon the evidence of the numbers to the square yard, 

 that the beds are either deteriorating or the reverse, especially as the comparison has been of but 

 two seasons. If, after they have been continued for some time, there should be an increased 

 number shown, it may be considered differently; but, as all experience testifies to the deterioration 

 of the beds, the inconsistency of the results shown by the table can probably be explained in 

 another way than by assuming the standard number to be too great, and this explanation will be 

 subsequently attempted. 



INFORMATION OBTAINED FROM " SPAT COLLECTORS." 



In order to ascertain when the first attachment of young took place ou each bed, the compara- 

 tive extent of such attachment, the influence of bottom and depth of water upon the attachment, 

 and, finally, the increase in size of the oyster and the number surviving each period of their exist- 

 ence, I placed early in July twenty -four spat collectors on the beds in the Sounds; but I regret to 

 say that the collectors were removed by some ill-disposed persons almost as soon as placed. 



The last hurdle, as the bundle of tiles was called, was in position on July 14, and on July 15 

 only four remained in position, and after the 1st of August there was but one left (No. 7, in the 

 Big Annemessex River). 



The hurdles were comiwsed of eight or sixteen half-round tiles, lashed on a wooden frame, and 

 so arranged that the frame rested on the bottom, the tiles being thus raised about six inches above 

 the bottom. The tiles were ordinary earthenware ones, unglazed, and were always placed so as to 

 have their concave side underneath. As long as the hurdles remained iu position they were fre- 

 quently examined in order to ascertain the advent of the young brood, and from those examina- 

 tions I am of the opinion that the first attachment of oysters took place about July 17, as on that 

 day we discovered, with the aid of the microscope, oysters on Hurdle No. 12, on Chain Shoal, and 

 on the 19th, in the same way, found them on No. 7, in the Big Annemessex. On July 24 they were 

 observable ou the hurdles on the Great Rock, both in shoal and deep water. Though the attach- 

 ment probably began about the middle of July, yet it was only evident on the tiles, as our dredging 

 operations did not discover any attachment before the 12th of August, when the young brood were 

 found in moderate numbers on all the beds in both the Sounds. 



The number found in Pocomoke Sound was much smaller than in Tangier, and the number on 

 the Upper Pocomoke beds and on the Muddy Marsh bed was smaller than on the lower ones. 

 The attachment appears to be proportional to the number of oysters, such beds as the Muddy 

 Marsh, for instance, having very few young; but as the bed is badly broken up, this may be owing 

 to the absence of proper cultch. The young appear to select the cleanest and smoothest shells for 

 attachment, and we always found that the u boxes," or those shells which had not been separated 



