2 MADRAS FISHERIES BULLETIN VOL. XI, 



notable are the scallops or pectens, the ear-shell (Haliotis), the true 

 cockle (Cardiiim) and the limpet (Patella). Examples of all these 

 occur on our Indian coasts but all are extremely scarce and in the 

 case of the very valuable Haliotis, the size seldom exceeds I^ inch 

 in length, as compared with the British, Japanese and Californian 

 species which vary from 4 to 6 inches in length. Several species 

 of Indian Cardium are larger than the British forms, but they are 

 seldom found alive, though dead valves are not uncommon on 

 Coromandel beaches. 



The need to protect the sources of supply from sewage contami- 

 nation must also receive careful attention; many shellfish from 

 their habits are liable to ingest bacteria from the water flowing 

 over the beds, and whenever this be heavily charged with sewage, 

 certain kinds, oysters in particular, which are often eaten either 

 raw or lightly cooked, may transmit the infection and cause enteric 

 fever and possibly other forms of bacterial disease. This point 

 will receive further attention when treating of the edible oyster. 



The following list and notes are not to be regarded as complete 

 and exhaustive ; lack of adequate skilled assistance has limited my 

 tours largely to the southern section of the Presidency and this has 

 prevented me from obtaining intimate acquaintance with many 

 important fishing localities on the Madras seaboard, particularly 

 with those northward of Pulicat Lake. To facilitate the identifi- 

 cation of the forms mentioned below, text-figures of the more 

 important are given. These are all original and drawn from life. 

 For the care taken in their delineation, much commendation is due 

 to Mr. M. Ramaswami Nayudu, B.A., my Shellfish Sub-Assistant, 

 who is responsible for the whole series. 



Catalogue of Madras Edible Molluscs. 



A. — Species in common use. 

 Pelecypoda or Lamellip.ranchiata. 



Species. English. Tumii. 



Mytilus smaragdinus ... ... Green mussel ... Kallikai ; Pach- 



chai uM. 

 Mytilus sp. ... ... ... P>rown mussel ... Kallikai. 



Area granosa ... ... ... Ark-shell... ... Vari matti. 



Ostrea virginiana ... ... Backwater edible 



oyster. )> Ali ; Piltti. 



Ostrea cucuUata ... ... ... Rock oyster 



