OE SOUTHERN INDIA. 405 



structure, but often they are so far worn down that to the naked eye the surface 

 appears as perfectly smooth. 



Locality,— 2 onAiGhQTTj, in a bluish sandstone ; ComarapoUiam and Veraghoor, 

 in a light coloured sandstone. 



Formation, — Arrialoor group. 



INOCERAMUS, Sowerby, 1822, (see p. 393). 



1. Inoceramus Cripsianus, Mantell, pi. XXVII, Eigs. 1—3, and PL XXVIII, 



Eig. 2. 



1822. Inoceramus OH^si^, Mant., Geol. of Sussex, p. 133, pi. 27, fig. 11; vide Zittel in Denksch. Akad., 



Wien, XXV, pt. ii, p. 95. 



In. testa cequivalvi, valde incequilaterali, elongato-ovata, plus minusve tumida, 

 antice breviter sub-rottmdata ; postice multo longiore, margine convexe truncato ; 

 margine ventrali leviter convexo, dorsali longo, recto, intus incrassato et foveolis 

 mmierosis ligament alibus instructo ; umbonibus tumidis, incurvis approximatis ; super- 

 ficie plicis rotundatis, crassis, fere cequidistantibus, et lineis concentricis confertissimis 

 et subtilissi/mis, nonnunquam paulo undulatis, notata. 



The variations which this species exhibits in India are perfectly the same as 

 those observed in the European fossil, of which Zittel gives so many character- 

 istic illustrations. Most common is the var. typica of Zittel, of a regular 

 elongated or oblong form and with strongly tumid valves (pi. xxvii, fig. 1). The 

 principal locality where this form occurs is the conglomeratic sandstone about 

 Karapaudy. 



A quite similar variety, represented in pi. xxviii, fig. 2, is characterized by a 

 lesser development of the concentric plications, and somewhat smaller and more 

 pointed beaks. This variety is found in whitish sandy beds north-east of Maithal. 



The flatter and more rounded variety (var. ^''egularis, d'Orb.,) occurs in the light 

 grey sandstones west of Arrialoor, and attains here often very large dimensions ; 

 specimens of 150 m. m. in length and about 125 m. m. in height are here not 

 uncommon. The same variety also occurs in the fine oolitic rock at Olapaudy ; 

 and also the mytiloid variety, with the anterior side very short and obliquely 

 sub-truncate, figured by Zittel as var. decipiens, is there associated with other 

 similar forms. 



Localities. — Olapaudy, west-east of Arrialoor, Maithal, north-west of Poodoor, 

 north-east and south of Karapaudy, &c. 



Formation. — Arrialoor group. 



J. Cripsianus is in South India a characteristic fossil of the uppermost series 

 of the cretaceous deposits, the Arrialoor group. In Europe the original form is 

 said to be from the Gault-beds of Sussex, but it has nowhere else been found 



