126 A HANDBOOK FOR SOUTHPORT. 



generally attached to corallines. Fine specimens are 

 about an inch and a half long, tubular, tapering to the 

 posterior end, and slightly curved ; perfectly white. 



Dentalium Tarentinum. The same remarks apply to this 

 species as to D. entalis, with the exception of the specific 

 differences. It is a thicker and straighter shell, the 

 posterior end marked with very fine raised lines, length- 

 wise, so fine as to require the aid of a microscope to 

 discover them ; they are the principal characteristic mark 

 of the species. 



Pileopsis Hungaricus. Shaped like the conventional cap of 

 Liberty. Many years ago, when tides were deep on the 

 foreshore, this was sometimes found, but is now ex- 

 tremely rare. Alterations in channels and sandbanks 

 influence the occurrence of shells. 



FISSURELLID^E. 



Emarginula reticulata. Rare. Found at high-water mark, 

 and amongst corallines. In shape like a cap of Liberty, 

 with a slit in the front margin. 



TROCHIADjE. 



Trochus zizyphinus (Top Shell). Moderately common. A 

 cone-shaped shell, granulated in narrow spiral bands. 



LITTORINID^. 



Littorina littorea (Periwinkle). One of the most abundant 

 shells on rocky coasts. Formerly uncommon at Southport, 

 but since the construction of the Pier may be found in 

 abundance. 



Littorina rudis. Rare. A smaller and lighter coloured shell 

 than the last. 



