92 



CRETACEOUS HOCKS OF S. INDIA. 



[Part II. § 1. 



The following is a rough field list of the genera found by Mr. C. M. Oldham and myself in 

 these beds : — 



CErHALOPODA. GASTEROPODA. 



Belemnites. Rostellaria (Alariar). 



Nautilus, Valuta, 



Ammonites. Natica. 



Turritella, 



Pleurotomaria. 



Cinulia. 

 Ancyloceras. Dentaliutn. 



JSaculites. Emarginula. 



Ptychoceras. Conchifera. 



Brachiopoda, Pecten. 



Terebratula. Ostrea. 



Area. 



Trigonia, 



Inoeeranius, 



Also one or two EeJiinida, Annelids, and Sqiialoid teeth (genus ?). Among the most common of 

 the Ammonites are A. latidorsatus and A. Mantelli, which species is extremely variable in form 

 and ornamentation. Other species of the Rhotomagensis section are also abundant. A. Eouy- 

 «?7MS occurs, though sparingly, and also A. Madraspatanus n. s. [M.S.S.J A, Julietti, Forbes, 

 (not D'Orb.) with a few other Pondicherry species. A. Timotlieanus, Mayor, is not uncommon, 

 and like A. latidorsatus, its more abimdant congener, is common to the green sands of Geneva* 

 I believe that the majority of the forms will eventually prove allied to or identical with those 

 of the gault and upper green sand, but I have noticed many exceptions, and the very 

 imperfect examination that I have yet made of this most interesting fauna, does not per- 

 mit me to generalize upon the question of age with any great confidence. The fossils occur 

 sometimes with the shell, more frequently as casts, and except some of the more fragile 

 forms, are for the most part iminjured. Certain bands abound in particular species, espe- 

 cially Ditrupa and Area, but for the most part the forms are much intermingled, and the 

 Conchifera almost always occur in single valves ; facts which look much as if some at 

 least of the fossils had been drifted into their present position. The Area bands are 

 chiefly coarse calcareous grits, frequently conglomeratic, and the 

 pebbles as well as the gritty matrix, consisting of gneiss debris, 

 must have required a tolerably strong current to move them. A few layers of similar conglome - 

 rate occur at intervals throughout this part of the group, but like the limestone bands, they are 

 rarely continuous beyond a few hundred yards. In one of these bands I found a rib, the only 

 bone met with about here ; except that it is probably either mammalian or reptilian, I can ofier 

 no opinion as to its nature. 



Between Odium on the one hand and Coonum and Permalpolliam on the other, courses of 

 calcareous grits, and conglomerates become more numerous, and 

 several peculiar forms of fossils not met with in the more Westerly 

 beds appear, replacing many of those characteristic of the latter beds. Some of the Cephalopoda 



Conglomeratic Grits. 



Beds to East of Odium. 



