O^ecklace-shells and Winkles 2 1 7 



Shetland, and off tlie coasts of Yorkshire, North- 

 umberland, and Durham. The Common Necklace- 

 shell {N. glauciiKi) is a pretty little species, plentiful 

 on sandy shores from low 

 water to great deptlis. The 

 shell is thick and solid, 

 highly polished ; the colour 

 varies from white to orano^e, ^ ,, , , 



P Common Necklace-shell 



and the markings — which 



are five spiral lines of V's and zigzags — vary from 

 orange to chestnut. There are 6 whorls, and the 

 spire is blunt. The umbilicus is contracted at the 

 mouth, and the operculum pale horn coloured. The 

 leno;th is little more than half an inch. 



Montagu's Necklace-shell (N. montacufi) is the 

 smallest of the native species. It is more globose 

 than the Common species, the colour usually fawn, 

 but varying to buff, often witli a whitish band along 

 the upper part of the 5 or 6 whorls, but free 

 from other markings. The spire, too, is shorter, the 

 umbilicus rounder and more open, and the operculum 

 rather more solid. It occurs at depths between 

 15 and 90 fathoms where there is a sandy or gravelly 

 bottom mixed with mud ; all round the Scottish, Irish, 

 and Manx coasts where these conditions exist, also in 

 the north of England, reappearing in Devonshire and 

 Cornwall. The Iceland Necklace-shell (K islandica) 

 differs from all the others in its less solid and semi- 

 transparent character, and by having the spire more 

 elevated. Beneath the dull yellow epidermis the shell 

 is white, without markings. There are from 5 to 

 7 whorls. The umbilicus is small, and the 

 operculum thin and golden j^ellow in colour. The 



