348 CEETACEOUS PELECYPODA 



all specimens, and sliould liave been better indicated in fig. 30, for which see the 

 corrected fig. 9 on pi. xlix. 



Localities. — Shillagoody and Olapaudy, in conglomeratic sandstone. 



Formalion. — Arrialoor group. 



2. AxiN^A LEVICULA, StoUczJca, PI. XLIX, Figs. 5-6. 



Ax. testa sub-orhiculata, (Bquilaterali, crassiuscula, iimbonihus parvis, tumidis, 

 valde aj^proximatis et area ligamentali brevi instructa, postice ad medium vix sub- 

 angidata ; valvis convexis, sub-levigatis, striis minutissimis et comfertissimis concen- 

 tricis et nonnullis siilcis incrementi 2')rofimdiorihtts, p)rop)e peripheriam sitis, prceditis, 

 snperficie prt?«^o erosa striis seu liitcis impressis, angusiis, radiantibiis notata ; 

 margine interno denticulato. 



Height of shell about equal to its length. 



Thickness of shell : its length ... ... ... ... 0-66 



This species differs from A. sthbplanata by its considerably more rounded form 

 and the greater convexity of the valves. In the perfect shell the surface is qviite 

 smooth, bvit when slightly worn off the usual radiating lines appear. The liga- 

 mental area is very small and very oblique, so that the beaks come very close 

 to each other. 



Localities. — Arrialoor, in soft whitish sandstone ; JBondicherry, in a greenish 

 grey compact sandstone ; rare. 



Formation. — Arrialoor group. 



3. AxiN^A ALTiuscuLA, StoliczJca, PI. XLIX, Fig. 9. 



Ax. testa snb-rotimdata, fere (cquilaterali, ji'^ululiim obliqua, altiore quam 

 longa, valva sinistra moderate convexa, crassa, siib-lcevigata, siilcis incrementi 

 2)recipne prope peripheriam distinctis, paulo irregulariter continuis, ijrcedita ; area 

 ligamentali latiuscida, valde declivi ; dentibus cardinis crassis, 9 in utroque latere, 

 elongatis, mediis multo minoribus ; margine interno denticulato. 



Height of left valve : its length ... ... ... ... 1'08 



Thickness „ : „ ... ... ... ... 0-20 



The somewhat greater height in proportion to length, the greater convexity 

 of the valves and solid structure readily distinguish this species from subptlanato, 

 and the first difference also holds good in a comparison with Ax. levicula. It is 

 closely allied to Zittel's Ax. norica from the Gosau, but less convex, apparently a 

 little more oblique, and without the distinct and coarse radiating striation which 

 characterizes the European species. 



Localities. — Ootacoil and Ninnyoor, in a pinkish limestone (evidently coral- 

 reef-limestone) . 



Formation. — Arrialoor group. 



