3°4 



LOWER FORMS OF MARINE LIFE 



tinuous distribution, being found in the Mediterranean and on the coast of New 

 Caledonia. 



The red whelk or buckie (Fusus antiquus), the largest of the British univalves, 

 ranges through the North Atlantic, North Pacific, and Arctic Oceans, the family 

 (Fasciolariidai) occurring in every sea. Another common British gastropod, the 

 dog-whelk (Nassa reticulata), resembles the last in belonging to a widely spread 

 genus ranging from the Arctic to the Antarctic in both hemispheres. In the same 

 group are included the murices (Maricidai), of which the wide-mouthed Purpura 

 patula is a well-known Mediterranean representative ; in this the ovate, blackish 

 brown diagonally furrowed shell is about 3 inches long. From its name it might be 

 supposed that the famous Tyrian purple was a product of this species, but this is 

 not the case, the dye being yielded by two species of the typical genus Murex. 



One of these is 

 the fire-horn (M. 

 brandaris), of the 

 shells of which 

 there is a vast 

 accumulation on 

 the site of the 

 ancient dye-works 

 atTarantoin Italy. 

 In length this shell 

 measures about Si- 

 inches, and the 

 colour is pale ashy 

 grey. 



The iridescent 



N*. 



X 



\ • '.- i . ' "V- 



A NAKED-HILLED GASTROPOD. 



..' ear-shells or or- 

 mers of the family 

 Haliotidce are the 

 representatives of 

 a group of uni- 

 valves distinguished from all the foregoing by the structure of the heart. Ear- 

 shells, which take their name from their enormous apertures, are iridescent 

 only on the inside, the outer side being rough so as to harmonise with the 

 rocks to which they cling after the manner of limpets, from which they may 

 be distinguished by their form and the row of perforations in the shell. The 

 common ormer (Haliotis tuberculoid), of the Channel Islands and the Mediter- 

 ranean, is offered for sale in the Italian fish-markets. Equally edible, but far 

 larger, is the giant ear-shell (H. tub if era) of the eastern Asiatic and Australian 

 coasts, the wrinkled shell of which is 6 inches or more in diameter and of a reddish 

 colour externally. Even more widely distributed are the limpets (Patellida), which 

 are found on the coasts of northern Europe, where ormers are unknown. The simple 

 unperforated conical form of the limpet-shell is sufficient to distinguish the group, 

 the members of which live between tide-marks and have one particular spot to which 

 they return daily after their wanderings in search of food. 



