24 • NEW YORK STATE MUSEUM 



thing to show that clams could be made to grow in this way. 

 The clam culturist could then make himself independent of 

 beach rights, and perhaps more easily obtain a lease of ground 

 for such a purpose below low w^ater mark. 



But one or two very small experiments on the soft clam have 

 indicated that the creatures do not do well under these conditions. 

 At Cold Spring a wire rack was constructed, and anchored above 

 the bottom in a swift current. Into it were put several hard clams 

 ranging from i^^ to 2|f inches in length. Every one of these 

 seemed to be in a healthy condition at the end of six months, but 

 not one had increased a particle in size. Not being able to cover 

 the body in sand, they seem to have remained most of the time 

 with valves closed. They may possibly have moved about at 

 times, for their shells were worn, but more likely this was due to 

 the fact that they were rolled about in the cage by the currents. 

 On their smooth, clean surfaces numbers of Anomias, or silver 

 shells, had attached and grown, as shown in figure 6. 



Though this small attempt to induce growth above the bottom 

 ended in failure, it should, on account of its importance, be 

 repeated on a large scale under as many different conditions as 

 possible, in the hope that some combination of circumstances 

 might prove to be the right one. 



Enemies 



Neither of the clams is molested by the starfish after it has 

 become large enough to burrow, though the very small soft clam, 

 and perhaps the hard clam also, is destroyed in great numbers by 

 small starfish, before it is able to cover itself. So far as I have 

 been able to discover, there is but one natural enemy of Venus 

 which might possibly be destructive. It is the gastropod mollusk, 

 Lunatia [fig. 7], which is abundant in some localities. It is found 

 in numbers at Cold Spring. On several occasions I have observed 

 it digging below the surface and attacking both hard and soft clams 

 in their burrows. By long continued labor, it files a smooth, clean 

 hole through the shell of its victim by means of a rasping organ in 

 its mouth cavity, and then destroys the soft parts of the body 

 within. Figure 8 illustrates the character of the borings on shells 



