OF SOUTHERN INDIA. 385 



3. Pinna laticostata, Stoliczka, PI. XXV, Pigs. 2-3, PL XXVI, Pig. 4. 



P. testa lanceolate trigona, antice tumida^ postice complanata^ margine dorsali 

 cum ventrali angulum circiter Zh^'-Z'S' formante, valvisfere uniforme convexis aut con- 

 vexiusculis, medio non fissuratis, costis 12-14, longitudinalihus, crassis distantibus, 3-4 

 ad marginem dorsalem approximatis, striis incrementi crassiusculis intersectis ornatis ; 

 regione latmscula inferiori, sen ventral% rugose plicata et striata. 



Shell rather elongately sub-trigonal, tumid near the beaks, and becoming gra- 

 dually flatter posteriorly. The valves are not fissured along the middle, ornamented 

 with from 12-14 strong distant ribs, crossed by rather distinct somewhat undulating 

 striae of growth. Three or four of the ribs are along the dorsal margin very closely 

 placed near each other, others reach beyond the middle on the ventral or lower 

 half of each valve, but a rather broad area along the ventral edge exhibits only 

 striae and somewhat irregular rugosities of growth. 



Localities, — ComarapoUiam, in a coarse grey sandstone, and Ootatoor, in a light 

 brown limestone. 



Formation. — Arrialoor and Ootatoor groups. Prom the last named group there 

 exists in our collection only one fragment of a large specimen with the shell surface 

 well preserved ; it entirely agrees with others from ComarapoUiam. 



4. Pinna intumescens, Stoliczka, PL XXVI, Pigs. 2-3. 



P. testa elongato trigona^ valde inflata, marginihus ad apicem angulum circiter 

 ZT formantibus ; valvis lateraliter convexis, antice continuis, uniforme curvatis, 

 postice sub-angulatis, intus furcatis, nonfiunquam prope terminationem posteriorem 

 fissuratis; parte superiore valvarum costulis longitudinalibus 6-7 instructa, inferiore 

 fere Icevigata, rugis et striis incrementi notata, 



A very tumid species with a large pedal opening below the beaks and strongly 

 convex valves. Near the anterior end these are uniformly convex ; then follows on 

 the internal side of the shell a deep depression, marked on the cast by an elevated 

 ridge (see fig. 2), and this continues to near the end of the posterior margin, some- 

 times showing a division between the two halves of each valve. 



Localities. — Odium, in earthy limestone. 



Formation. — Ootatoor group. 



5. Pinna consobeina, d'Orbigny, PL L, Pig. 4. 



1847. JPinna consohrina, d'Orb., Voy. Astrolabe, Paleont., pi. v, figs. 39-40. 



I have given a copy of d'Orbigny' s figure merely to complete an account of 

 the shells noted from the South Indian cretaceous deposits. D'Orbigny's figure 

 indicates a species which is very narrow and long ; the ornamentation is similar 

 to that of P. complanata, but if d'Orbigny's figure is correct and drawn from a 

 good specimen, it cannot be considered as representing the same species. I was 

 not able to find d'Orbigny's original in Paris. 



