414 PHOLADACE^; SOLEN. 



rior extremity, and by the length and union of the respiratory 

 tubes. Their habit is to burrow much more deeply ; and their foot 

 is made to project rather from the anterior extremity, than from 

 the middle of the body ; so that the form of the whole is more 

 cylindrical than we have yet seen it. The Solen, or Razor- 

 shell, is a well-known example of this group. It has an elongated 

 shell of which the hinge is furnished with distinct teeth, and the 

 ligament is altogether external. The animal burrows in the 

 sand, into which it sinks rapidly on the approach of danger. It 

 seldom or never quits its hole ; and its movements are nearly 

 limited, therefore, to an ascent or descent in it. This it ac- 

 complishes by means of its foot, which it elongates and at- 

 tenuates into a point, when it wishes to bore ; contracting it 

 into a rounded form, so as to fix it by its enlargement within 

 the hole, when it desires to rise. The animal is sought for by 

 fishermen on some coasts, as a bait for certain fish. Its burrow 

 is often recognised by the little jet of water which the animal 

 throws out, when alarmed by the shaking of the sand occasioned 

 by the motion of the fisherman above. When the tide is low, : 

 the holes are often seen in considerable numbers ; and this is 

 also the time when the animal may be most easily procured. 

 The fisherman throws a little salt upon the hole, which induces 

 the animal to ascend, according to some, by leading it to the 

 belief that the tide had returned, and, according to others, by an 

 irritating effect of which it desires to get rid. To seize it when 

 it makes its appearance, some address and quickness are required ; 

 for it speedily returns to its burrow ; and, if entrapped, its 

 struggles are sufficiently powerful to cause injury by the sharp 

 edges of the shells. If it re-enter its hole, fresh pinches of salt 

 no longer produce the same effect ; the animal having either 

 learned by experience that they do not indicate the return of the 

 sea above it, or deeming it better to submit to the irritation than 

 to expose itself to capture. The fisherman then has recourse to 

 a long iron crook, which he sinks pretty deeply ; and, drawing 

 it out obliquely, carries away the sand, and the Solen contained 

 in it. If he should fail in this attempt, he knows that to try 

 again would be useless ; since the animal instantly burrows 



