338 JOURNAL, BOMBAY NATURAL HISTORY SOCIETY, Vol. VITT, 
Arca granosa (Lam.)—Shell nearly equilateral and strongly ribbed 
with about 20 noduled ribs. 
Kpidermis brown, thin, and scaly. Shell pure white. 
_Sizerdle x ae 
Arca japonica (Reeve).—Shell oblong, very inequilateral, shining 
white, with 32 to 33 broad flat ribs. 
Size 13” & 1”. 
Area tenebrica (Reeve) isa small oval flattish shell with the hinge 
line slightly curved. The ribs are close set and very numerous. 
Size $” X 4", but I have one specimen #” X 3”. 
Arca ae (Linn.) is the smallest of the family and very common 
amongst shell shingle. White or yellow tinged, hump-backed and 
somewhat squarely shaped, with the umbo curling over the ligamental 
area. Radiate ribs numerous and somewhat beaded. 
Size 3” x }, 
LUCINACHA. 
We have two specimens of this family which are so widely different 
in every respect that it is hard to believe they are correctly classified. 
Cardita antiquata (Lam.) is one of our commonest shells. Very 
massive, white beneath, with a yellow-brown epidermis, and with irre- - 
gular burnt blotches or streaks scattered over the radiate ribs, Ribs 
broad, and about 23 in number. Hinge remarkable for long ridge, 
which fits into a corresponding groove. 
Size 24” x 2". 
Diplodonta indica (Desh.) is a very delicate white globular little 
shell, smooth and shining, or very finely concentrically striated, 
About the size of a small marble.* 
CYPRINACEA., 
Cardium asaticum (Brug.)=coronatum (Speng.)—This is our re« 
presentative of the cockle family, and the double shell viewed side- 
ways gives a perfect outline of a heart. The ventral border is semi- 
circular. Shell light yellow and deeply ridged, with 33 to 34 radiate 
ribs, which are notched or lamellated towards the ventral border. 
Hinge, central teeth small, but two sharp pointed prominent ones on 
either side, widely separated from the others. 
* N.B.—Dr. Fischer puts this shell under the Ungulinide.) 
