28 REPORT OF COMMISSIONERS OF INLAND FISHERIES. 
It was very apparent in these cases that the abundance or 
scarcity of the set was not due to the quality of the soil nor to the 
quantity of old clams in the vicinity, nor yet to the absence of 
enemies, but was due probably to the position of the shore with 
reference to the tide currents. Some of the areas where the set 
was exceedingly thick were, moreover, far from being the best for 
adult clams, and the reason is not far to seek. In one case a cer- 
tain point of shore was set in the middle of July as thickly as the 
clams could burrow, but by the ninth of August hardly a young 
clam could be found. They were apparently washed out or were 
covered with shifting sand. In another locality, about 40 rods 
from the last, the set was discovered on July 5 and was also very 
thick. These clams continued to be abundant throughout the 
summer and autumn, and, though meanwhile they were somewhat 
thinned out, were yet very numerous on December 4. The 
thinning out began in July, and from this time until September 
there was always a wind-row two or three feet wide of small clam- 
shells along this portion of the shore. Very often among these 
shells one would find live clams and preying upon them a whole 
army of star-fishes, crabs of various species, and mummichogs. 
Undoubtedly the crabs, especially the blue crabs “ paddlers,” and 
some other animals dig up or uncover the young clams and scat- 
ter them about where they fall prey to many enemies; but I think 
one important factor in their wholesale destruction les in the fact 
that they set much thicker than they can grow and a great many 
are crowded out, or, at least, if they are once brought to the sur- 
face of the ground, cannot burrow again. When the clams are not 
more than one-fourth of an inch long—early in July—they were 
near together, but when by the last of July they had become sev- 
eral times longer and many times the bulk, they actually touched 
each other; for at this period they all buried themselves to about 
the same depth. As one walked over the ground, or tapped it, the 
whole surface for a yard or two would move perceptibly as the 
clams contracted. 
A more definite notion of the abundance of the clams in the 
