182 CRETACEOUS PELECYPODA 



intus stihtiUssime striatis separatis tecta. Cardo dentibus siciti in specie lypica 

 instruct US. 



Leu^h of largest specimen ... ... ... ... 25 m. m. 



Height : len<^th ... ... ... ... 0-98 - 1-0.5 



Thickness : heifjUt ... ... ... ... 0-30 - 032 



This is an almost perfectly orbicular species, very flat and compressed, 

 slightly tumescent at the umbones, -n-hich are pointed and strongly incurved, 

 touching each other. The lunula is elongately ovate and very deep ; a separate 

 area can hardly be said to exist, the fulcra supporting the ligament Mng in a 

 very narrow fissure with perpendicular sides. The ornamentation is pecviliar, the 

 whole surface being covered with sharp concentric sometimes almost laminar thin 

 ribs separated by broader interspaces, which are attain very minutely striated. The 

 width of the sulci .slightly varies, and they are less conspicuous when the ribs 

 are somewhat undulating. 



Porbes had figured this species under the name of Art. lentictdaris, but in 

 his description he mostly had in view specimens which actually were identical with 

 the European species ; his reference to the recent Art. lincta, Pult., also clearly 

 indicates this. 



Locality. — Niunyoor, in a white earthy limestone ; rare. 



Formation. — Arrialoor group. 



3. Eriphyla diversa, Stoliczka, PI. VI, Fig. 6. 



Eriph. testa quadrangulariter rotundata, crassitiscida, concentrice numerosissinie 

 t^t anguste lirata, convexiuscula ; timhonibus valde prominnlis, acutis, paulo incurvis ; 

 decUvitate lunulare ad marginem profunde excavata, areale fere rectiiisctUa ; liinida 

 et area profundis, prima ovali, altera elongata, postice anrjustissima. 



Height : length ... ... ... ... 0'96 



Thickness : height ... ... ... ... 0-44 



This form greatly resembles in shape the more convex varieties of Erij)h. 

 lenticularis, but the beaks are more prominent and pointed, and the surface is 

 covered with rather strong very close ribs ; one or two deeper sulci being only 

 slightly indicated ; the ornamentation is, however, characteristically difi'erent from 

 that of the above-named species. 



Locality. — South-east of Vylapaudy ; only a single specimen was found in a 

 greyish somewhat conglomeratic rock. 



Formation. — Arrialoor group. 



