124 MADRAS FISHERIES BULLETIN VOL. XIV, 



dead shells seldom get damaged when they are washed ashore. 

 The two Madras species are Doliiim maculatum and D. olcarium. 



The Fig-shells {Pinila) are so named because of their shape. 

 Their habits are the same as those of the Tun-shells — they live on 

 sandy bottom not far below low-tide mark ; to enable them to crawl 

 rapidly and comfortably over soft unstable sand, the foot in both is 

 very wide, forming a broad flat sole (fig. 14), In Pirula this is 

 particularly wide and both the upper surface of this foot and the 

 mantle folds that more or less enwrap the back of the shell, as in 

 the cowries, are beautifully veined. (These dorsal folds are not 

 present in the case of Dolium.) 



Dead examples of the STAIRCASE-SHELL, Solarium, are fairly 

 common on sandy beaches around our coasts after storms. The 

 shell has a handsome low spiral not unlike Xenophora in general 

 form, but orbicular in outline when viewed from above, the last 

 whorl angular at the outer edge ; a deep pit or umbilicus passes 

 down the centre of the columella on the under side of the shell. The 

 projecting edges of the whorls seen on the sides of this umbilicus 

 have been fancifully compared to the windings of a spiral 

 staircase. 



RACHIGLOSSA. 



The family Turbinellidas is of special interest in India, for the 

 type genus is TiirbincUa, the Sankha or Chank, a shell around 

 which has gathered more legend and folk-lore than around any 

 other in the world. Other important genera are Cynodo/itn and 

 Melon gen a. 



The Chank {Tnrbinella pinim) is a peculiarly Indian species. It 

 occurs nowhere in Asia outside of India and the Andaman 

 Islands, its nearest relatives living on the Brazilian coast. Its 

 finest or central variety is distinctly fusiform or spindle-shaped, 

 with a handsome, well-balanced spire, but this may be depressed 

 so greatly in some varieties as to give a distinctly piriform or 

 pear-shaped appearance. The mouth is wide and prolonged 

 anteriorly into a long deep canal lodging the great siphon used 

 apparently in sensing the presence of the worms which form its 

 principal food. The columella bears three and sometimes four 

 strong ridges to which the very strong columellar retractor 

 muscles are attached. Individuals living in shallow water, where 



