OT SOUTHERN INDIA. 235 



CHAMA, Llnne, 1758, (vide p. 230). 

 \/ Chama deplanata, Stoliczka, PL XXII, Pig. 5. 



Chama testa ovata, mutto attiore quam tonga^ valde depressa ; valva inferiore 

 omnino adriata, ptana, ad mm^ginem superiorem paulo elevata ac lameltosa ; valva 

 siiperiore sinistrorsa, paululum convexiuscula, in superficie dense spinulose lamellata, 

 spinis sub'CEqualibus in seriebus costuliformibus radiantibus dispositis, apice acuto, 

 lateraliter incurvo instructa. 



Height of shell : its length ... ... ... ... 1.31 



The single specimen of this remarkable species is distinguished by its very 

 depressed and high form in proportion to the length of the shell. The lower valve 

 is attached in its entire extent, only the upper margin is somewhat raised and 

 slightly incurved towards the upper valve, which is finely spinulose and radiately 

 costulated all over, the beak being lateral, pointed, and incurved. The ornamenta- 

 tion quite agrees with that of many recent species of Chama. 



Locality. — Anapaudy, in a brownish calcareous sandstone ; apparently very rare. 



Formation. — Trichinopoly group. 



y Caprotina conp. Cenomanensis, d'Orb., PL XXII, Pig. 2. 



A single upper valve was found in a conglomerate east of Kaudoor ; its rounded 

 form, moderate convexity, sub-terminal incurved apex, and numerous sub-equal 

 rather sharp radiating ribs do not show any essential difference from those of the 

 upper valve of Gaprotina Cenomanensis fBequienia idem, d'Orbigny, Pal. fran9. 

 terr. cret., vol. iv, p. 261, pi. 595, figs. 1-di). 



The ribs in the Indian specimen are probably a little sharper., but this may 

 be owing to the weathering off on the surface. Until more and better preserved 

 specimens have been found, it appears safest not to introduce a new specific 

 denomination. 



The two hinge-teeth are distinctly visible in the valve, the posterior tooth is 

 slightly larger, and an oblique rib runs from it almost parallel to the margin ; it 

 is probably the one which is required for the attachment of the posterior muscle. 



Loca lity . — Kaudoor. 



Formation. — Arrialoor group. 



XXI. Family,^ CJSAMOSTEEIBJE. 



The animal of the single genus and species belonging to this family, Ch. albida, 

 Lamarck, has the mantle margins perfectly united with a narrow opening for 

 the foot, which is rather small and somewhat compressed, almost rudimentary as in 

 Chama ; the two siphons are very short with fringed orifices, the palpi are long and 

 obtusely pointed ; the gills are stated to be single, but the lateral groove showing 

 the unequal portions of the leaves is distinctly seen in Hancock's figure. 



3 M 



