192 



MADRAS FISHERIES BULI ETIN 



VOL, XIV 



Fig 54. Vazhukkumatti {l^aft's 

 ceylofietisis). X I. 



chevrons on a yellow ground. Other smaller species as T. pingiits 

 are fairly common on both our coasts, but with the exception 

 of Tapes ceylonensis, they are seldom to be found alive unless 

 very diligent search be made, or a shell dredge used. 7- 

 ceylonensis departs greatly from the typical compressed Tapes 

 form. It is a handsome inflated species, with a superficial resem- 

 blance to the Backwater Clam 

 [Mcrctrix casta), being about the 

 same size, shape and colour; it 

 differs, however, in having radiat- 

 ing bands of a reddish brown tint 

 running from the umbo to the 

 margin. The pallial sinus is 

 much better marked, and is deep 

 and angular. Average length 

 l^/i inch. In the neighbourhood 

 of Pamban, where it is called 

 Vazhukkumatti, it is found and 

 fished with the Se-vala Diatti [Mactra corbicidoidrs). It is also found 

 on the West Coast, at Cannanore, Tellicherry, and elsewhere. 

 Flatter and more like a true Tapes is Paphia malaharica, strong'i\ 

 ribbed, but in its colour closely related to T. ccylo)icnsis. 



Closely allied to Tapes, are the pretty SUNETTA shells. 

 Detached valves are conmion on our sandy beaches, and maybe 

 recognized by their coarse concentric ribbing and the attractive 

 colour design, usually some arrangement of bold reddish brown 

 chevrons ; a fine milling occurs just inside the ventral edges of the 

 valves. They are small shells seldom exceeding i3^ inch in length. 

 5. meroc and S. ejfcssa are two common species. 



The true COCKLES {Cardiidae) are represented in Indian seas 

 by several large and handsome species, notably the Asiatic cockle 

 {Cardium asiaticum) found on all our sandy coasts. This species 

 is thin-shelled and highly inflated, with the exterior sculptured 

 with fine ribbing. In size it runs to two inches in depth, the length 

 being appreciably less. The foot is very large, bent in the middle 

 nearly at a right angle; it is used for leaping and some species can 

 jump a foot or more from off the bottom. Unlike the thick-shelled 

 and smaller common cockle of European seas, none of the Indian 

 cockles has any appreciable economic value, as they do not appear 

 ever to occur in thickly-populated beds. 



