290 CRETACEOUS PELECYPODA 



Ast. similis (vide Zittel in Denksch. Akad., Wien, xxiv, pt. ii, p. 157, pi. 8, fig. 6), 

 though I am not certain whether the two forms are really specifically distinct. 

 Miiller's ccelata does not differ by its triangular form from, similis, as would be 

 expected from that author's figure, but both are almost quite identical in form. 



Locality. — Monglepaudy, in a grey calcareous sandstone; apparently very rare. 



'FormMion, — Ootatoor group. 



2. GouLBiA TRiGONioiDBS, StoUczka, PL X, Pigs. 4-8. 



G. testa S'uh -triangularis postice conspimiiter angustata et ad terminationem 

 truncata, moderate conipressa sen pernio tiimtdula, angttlo plus mimtsve distinct o ab 

 nmhonihus ad marginem postero-inferiorem decnrrente notata, costiilis 10-12 crassi- 

 usculis concentricis, in regione liinulari et areali ohsoletis ornata, margine interna 

 minutissime denticulato ; cardine in valvula dextra dentihus trihus cardinalihus, 

 duobus anterioribiis crassis sub-cEqualibus, postico sub-obsoleto, et uno longo laterali 

 antico instructo ; impressionibus musculartbus profundis, ovatis^ imp. postica 

 paiilulum ma j ore quam antica. 



Heig-lit of shell : its lengtli ... ... ... 078 - 0-82 



Thickness „ : „ ... ... ... 0-55 - 0-60 



This species is readily recognised by its posterior narrowly truncate form. 

 The thickness of the shell varies, and so does also the number of the ribs, but 

 even if the latter are present in nearly as small a number as in Q. planissima, 

 there is always in the present species a slightly raised angular ridge observable 

 extending from the beaks to the postero-inferior margin. Some of the more 

 elongated specimens strongly resemble small concentrically ribbed species of 

 Trigonia. The lunula and area are always well marked and surrounded with 

 raised sharp edges, the ribs not extending on them. The hinge has in the right 

 valve the two anterior cardinal teeth about equally strong and the posterior is 

 almost obsolete, while in planissima the anterior cardinal is much smaller than 

 the central one. 



Locality.- — East of Anapaudy, in brownish sandstone ; not common. 



Formation. — Trichinopoly group. 



CARDITA, Brug., 1789, (see p. 283). 

 1. Caudita Jaquinoti, d'Orb., PL X, Eigs. 15-21. 



1846. Cardita orbicularis, Forb., Trans., Geol. Soc, London, vii, p. 144, pi, xvii, %. 11, (non idem, Sow., 1825). 



1846. „ striata, „ „ „ „ „ „ „ pi. xiv, fig. 1, (non idem, Sow., 1815) 



1847. Cardium Jaquinoti, d'Orb., Voy. Astrolabe, Pal., pi. v, figs. 23-25. 



1850. Cardium Jaquinoti, suh-striatum et orhiculare, d'Orb., Prod, ii, p. 242; — eadem auctorum. 



Card, testa orbiculato quadrangulari, paulo longiore quam alta, tumida, incequi- 

 laterali, umbonibus incurvis, approximatis, fere terminalibus instructa, superficie 

 multicostata, costis ternatis parte medlana m,axime elevatis et spinulose tuberculatis 

 sulcis profundis fere cequidistantibus separatis ; cardine in valva dextra dentibus 



