OF SOUTHEEN INDIA. 175 



usually prominent and pointed; the concentric ribs are comparatively strong; 

 the lunula is very narrow, only indistinctly marked by a shallow depression ; the 

 area is also narrow, but deep. The hinge-teeth offer no peculiarity; they are 

 short, and the middle one of the three cardinals is the thickest ; the lunular tooth 

 is elongated. This species bears some resemblance to Forbes' Vemis Arcotensis 

 (Cytherea), but the ornamentation is totally different. >. 



Locality. — Ninuyoor, in a white earthy limestone. 



Formation. — Arrialoor group. 



9. Cytherea [Callista] discoidalis, Stoliczka, PL VII, Figs. 30-31. 



Cyth. testa late seu rotundate ovata, antice ac infra rotundata, 2oosfice angtista- 

 tim stib-trimcata ; declivitate limulare concaviuscula, areale moderate eurvata ; lunula 

 parva, angusta, impressa ; area longa, angusta, excavata, marginibus acutis circum- 

 data ; fulcris longis, crassis sed profunde sitis ; valvis moderate convexiusciilis, sub- 

 discoidalibus, liris crassitiscidis ac interspatiis sub-latis profiindis separatis omnino 

 notata. Cardo dentihus tribiis cardinalibus, brevibus, in utraque valva crassis 

 instructus ; dente lunnlare elongate. 



Length of largest specimen ,.. ... ... ••■ 24 m. m. 



Height : length ... ... ... .•• O'S? 



Thickness: height ... ... ... •.. 060 



The more flattened, roundish, and almost discoidal shape of this species readily 

 distinguishes it from the last. The concentric ribs are strong and the interspaces 

 broad, though not as broad as the ribs. 



Locality .—Wirmjoov, in a whitish, earthy, and in a conglomeratic limestone. 



Formation. — Arrialoor grovip. 



10. CrTHEKEA [Callista] minutula, Stoliczka, PI. VII, Figs. 18-20. 



Cyth. testa late ovata, compressiuscula, x>rope ttmbones tumescente, sub- 

 incequilaterali, antice rotundata, p)ostice angustatim truncatula ; declivitate lumdare 

 concaviuscula, areale convexa, ad marginem ventralem regulariter convexa; concentrice 

 eleganter lirata : liris crassis plus minusve obtusis et sulcis (equidistantibus seu 

 inierdum latioribus atque subtilissime striates separatis. Cardo dentibus cardinalibus 

 tribus in utraque valva, duobus anticis brevibus, crassiuscuUs, furcatis, postico tenui 

 elongato, et dente lunulare in valva sinistra mediocri, ab ceteris distantiori, fossa; pro- 

 fundcB in valva dextra congruente instructus. 



Length of largest specimen ... ... ... ••■ ll'S m. m. 



Height : length ... ... ••• •■• 0'^^ 



Thickness : height ... ... •■. •■• ^'SL 



This is a very elegant, small, and rather compressed shell, more or less broadly 

 oval, anteriorly roimded, posteriorly slightly and narrowly truncated ; only near 

 the beaks the valves are a little more tumescent, flattening out very gradually, so 

 much so that larger specimens would no doubt have the appearance of very flat 



