999 CllETACEOUS I'ELECYrODA 



this peculiar form from any otlicr known. The concculric stria) arc very clistiiiet, 

 especially on the strong convexity near the umboncs; they are less so in the niithUe, 

 but become again more strongly marked near the periphery. The radiating ribs 

 are numerous, close together, and also traceable on the internal surface of the 



shell. 



Xoc«Z^7y.— Monglepaudy and Ootatoor, in a grey calcareous sandstone ; appa- 

 rently a rare shell. 



Formaliou. — Oolatoor group. 



FE-AGUM, Bolten, 1798 (vid(! p. 210). 



1. PiiAGUM PKyECirRiiENS, StoUczlcci, PI. XI, Eigs. 1-2. 



Fmg. testa oblique stih-qiiadranynlari, siih-cordata, soUda, nmbonibiis luthiscnUs, 

 promimilis, valde incnrvis, siih-medianis, antice aiKjiistalun rotundata, infra Icnta 

 convexa, post ice rcctiuscide ao oblique irniicata; in siiperjicie costis 35-15 radi- 

 antibus sub-ceqmdibus, sulcis jjrofundis angustissimis disjimctis, ornata ; costis anticis 

 ac lateralibus, seu medianis, in junioribiis spccimiuibus lamcllose-, in adultis sub- 

 rotundate- tuberculosis. Us in decUvitate postica sitis distantioribm et sub-lccvigatis ; 

 lunula angnsta, Icevigala ; f uteris crassis, 2^>'omimdis ; margine interno crasse 

 dentato; cardine dentibiis curdinalibus et lateralibus sicut in speciminibus iypicis 

 instructor impressionc paUiali postice conspicue truncata seu lente simiata. 



Jloi-lit of slicll : its length ... ... ... O'SO 



TLickucss „ : „ ... ... .■• ^''^ 



This is a typical species of the sub-genus Fragmn, wliich has scarcely becji 

 known before from cretaceous rocks. The form is longer and less high than most 

 of the recent species, and the radiating ribs are hardly tubereulated at all on the 

 posterior declivity ; the shell close below the posterior muscular impression is 

 strongly thickened and the pallial line is truncated or slightly sinuatcd posteriorly ; 

 in every other respect it agrees Avith the type species of the above genus. 



Locality. — In calcareous sandstone north of Odium and west of Anapaudy; 

 at the last named locality chiefly small specimens, but in very large numbers, occur. 

 They are extremely like a little species which lives at present very abundantly 

 on the coral reefs of the Nicobar islands, and apparently never grows to a largo 



size. 



Formation .— Ootatoor group. 



