42 INLAND FISHERIES. 



Class 1. Set of 1899 planted in heds on shore, Nos. 1-9. — Tlie 

 clams were assorted according to tlieir size, and tlieir size is re- 

 corded in terms of tlie number per quart. 



In tlie tables tlie column at the left sliows the conditions at plant- 

 ing, and those at the right the results at the time of digging, with 

 the rate of growth. 



It was hoped that the difference in the rate of growth at half- 

 tide and low-tide marks could be shown by these experiments, 

 but the clams planted at low tide fared like those in experiment 

 5, i. e., they were nearly all dead when examined in the summer, 

 the empty shells, however, showing that they had lived about two 

 months and that the mortality was sudden, although the cause is 

 not known. 



The results as they stand have some interesting features. A 

 glance at the last column shows that the increase in bulk averaged 

 from 9 per cent, to 32 per cent, per week. Upon comparing the 

 dates of digging it will appear that the specimens dug up early in 

 the season have the smaller average increase ; in other words, the 

 growth is more rapid in the latter part of the season. This may 

 be accounted for by supposing that the clams grow faster after 

 they spawn. 



Class 2. Planted in boxes, JVos. 10-14-. — These clams fared as 

 badly as those planted in the beds — a sudden death carried them 

 off after they had increased to about twice their original length. 

 By comparing the two more successful experiments it will be 

 noticed that the clams which were covered all the time by water 

 increased more rapidly, a result in harmony with the conclusions 

 arrived at the previous year, and stated in the last report, viz. : 

 that the growth of the clam is more rapid when they are sub- 

 merged a greater part of the time. 



Class 3. Wire boxes. — The unfortunate experiments of this class 

 speak for themselves. 



Class 4- Set of 1900 in boxes, No. 25 and 25a. — These experi- 

 ments are satisfactory and instructive. They are remarka»e, also, 

 since the boxes containing the first four experiments were of the 



