208 



THE SEA SHOBE 



round and polished. The mantle is quite open at the anterior end, 

 and its margins are fringed ; the foot is flattened and tongue- 

 shaped ; and the siphons, which are quite separate, are generally 

 long and slender. 



In the typical genus (Tellina), of which we represent two 

 very common British species, the ligament is very prominent, and 

 the slender siphons are often much longer than the shell. The 

 members of this group move very freely, travelling about by 

 means of a broad, flattened foot. 



The shells of the genus Psammobia are popularly known as 

 Sunset shells, being prettily marked with radiating bands of pink or 



FIG. 141. TellinidcB 



1. Psammobia ferroensis. 2. Donax anatinus. 3. Tellina erassa. 4. Tellina tenuis. 

 5. Donax politus 



other tint, reminding one of the beams of the sun when setting 

 in a cloudy sky. In these, too, the ligament is very prominent, 

 and the shell gapes slightly at both ends. 



The same family contains the pretty little Wedge shells, which 

 are so called on account of their triangular form, and constitute 

 the genus Donax. These shells, which are seldom much over an 

 inch long, are very common on some of our sandy beaches, being 

 washed up in considerable numbers after the animals have died, 

 but the specimens are seldom perfect. The molluscs themselves 

 are burrowers, and live in the sand, at and just below low-water 

 mark ; and, as they usually burrow to a depth of only a few inches, 

 are easily obtained alive. 



