196 



Shell Life 



on the coasts of Dorset, Devon, Cornwall, and the 

 Channel Islands. The Large Slit - limpet {E. 

 crassa) is much larger than the last two species ; 

 the white shell measuring IJ inches in length. It is 

 a less elevated cone, and the radiating ribs number 

 between 80 and 100, alternately broad and narrow, 

 each of the former often divided into three. In 

 addition to the concentric wrinkles that cross these, 

 there are radiating rows of minute glistening dots. 

 The mouth of the shell is oval, and is notched in 

 aofreement with the ends of the ribs. It has 

 been found under stones at Oban at periods of ex- 

 tremely low water, but otherwise only by dredging 

 on rocky ground off* the west coast of Scotland, 

 Shetland, Antrim, and Dublin, in from 20 to 75 

 fathoms. 



The Ormer or Sea Ear (Haliotis ttthercidata). 

 The claims of this mollusk to be included among 



native species are 

 political rather than 

 natural, for its only 

 " station " north of 

 St. Malo is the shores 

 of the Channel 

 Islands, where it is 

 used for food, after 

 being beaten to make 

 its muscular foot 

 tender. Flat and shallow as the reddish-brown 

 shell is, it is distinctly spiral, with the last whorl 

 very large. Its exterior is rough and shabby- 

 looking, but it is lined with the iridescent " mother- 

 o'-pearl " which makes these shells so valuable to 



Ormer (one-fourth nat size) 



