4 CRETACEOUS ROCKS OF S. IXDIA. [PaRT I. 



to the present time, but little has been added to the facts they contain, 



however subsequent authors may have differed from Professor Forbes in 



the conclusions to be drawn therefrom. 



The following remarks, extracted from Professor Forbes's report, and 



quoted in extenso, will best express the opinions of that eminent author. 



" 1st. — The tlii-ee deposits, viz. Pondiclien-y, Verdachellum, and Trinconopoly, des- 

 cribed by ]\Ir. Kaye, are Cretaceous, inasmucli as there are 



His conclusions. . . . ^ „ ., . , m • n 



characteristic known Cretaceous lossils in the collections irom 

 all of them, whilst no fossils of any other system occur. The nearest allies of the ma- 

 jority of the new species are Cretaceous ; and among the genera and sub-genera are many 

 which, as far as we know, are confined to, or have their chief development in, the Cre- 

 taceous system. The three deposits are connected with each other zoologically by the 

 associations of certain species common to two of them, with others found in the third. 



27id. — Two of the three deposits, viz. Verdachellum and Trinconopoly, are of a dif- 

 ferent epoch of the Cretaceous era fi-om the third, Pondicherry. The two former have 

 several species in common, (and those sjiecies among the most prolific in individuals), 

 which are not found in the third. In them are found almost aU the species identical 

 with European forms. In several of the genera, of which there are many species, the 

 forms are altogether distinct ; although, judging from the evidence afforded by mineral 

 chaj-acter and association of species, the conditions of depth and sea bottom at the time 

 of the deposition of the strata seem to have been the same. The difference therefore 

 must have depended on a representation of species by species wi time and not i7i depth. 



37'd. — The beds, ajjparently contemporaneous, viz. Trinconopoly and Verdachellum, 

 may be regarded as equivalent to the Upper gi-een-sand and Gault, the European 

 species they include being either characteristic Upper green-sand and Gault forms, or 

 else such as occm- in those strata. The new species they contain are either closely 

 allied to known Upper green-sand or Gault species, or peculiar to the Indian beds. 



4ith. — The Pondicherry deposit may be regarded as belonging to the lowest part of 

 the Cretaceous system. In it almost all the fossils are new. Such as ai-e analogous to 

 known species, are allied to fossils of the Lower green-sand of English Geologists and 

 Neocomian of the French. In the genus most developed in this deposit, viz. Ammo- 

 nites, three-fourths of the species belong to those sub-genex-a, specially characteristic 

 of the "Lower Neocomian" of the Mediterranean basin, whilst of the remainder, as 

 many representatives of Oolitic fossils occur as of Upper green-sand. The resem- 

 blance between the Ammonites of this part of the collection, and those of CasteUane 

 in the South of France, is very remarkable, though the specific identity of any of them 

 is doubtful. Having seen no account of the Conchifera of the CasteUane beds,* I 

 cannot say how far the analogy is borne out among the bivalve MoUusca among the 

 Indian species, of which there are many very peculiai* forms." 



* The 3rd Volume of the PaleontoJogie Frangaise of M. D. Orbignj, containing the 

 Conchifera of tlic Cretaceous rocks of France, was not completed until 1847, three vears 

 after the puhlicatiou of Professor Forbes' paper here quoted. It was commeuced in 1843. 



