Chap. IY.] trichinopoly district — plant beds. 49 



beds formed a distinct formation, the iDferonce must stand for what it is 



Cycadaceous wood of worth, until re-examination may prove it to be erro- 

 Ootatooi- Group. . • • ^ ^ ^ . 



neous. Agam some specimens of wood from the 



Ootatoor formation, which* I submitted to Dr. Thomson, were pronounced 

 by him to be Cycadaceous, so far as he could judge from inspection and 

 without examining microscopic sections : and, thirdly, my colleao-ue 

 Mr. Foote, detected what appeared to be a portion of a Zamia frond in 

 the bottom beds of the Trichinopoly Group near Alundanapuram. 



With these remarks I may now leave the matter to be decided by 



Objections by no means ^^^^^^^^ evidence. The facts I have brought forward 



are not, I admit, at all conclusive inthemselves as 



bearing on the question at issue, but still they offer at least one difficulty 



to be removed, before we can admit the lower Oolitic age, assioned 



to the beds by Dr. Oldham, to be an accepted truth. 



Ifote hy Mr. Oldham. — In the summer of 1859, at which time consider- 

 able j)rogress had been made in mapping the districts now rej)orted on, 

 I visited Trichinopoly, and went over the greater portion of these Creta- 

 ceous rocks in some detail. Among other points in which I was much 

 interested, I examined all those localities along the western boundary 

 of the Cretaceous rocks, where the j)lant-bearing beds had been noticed 

 from Ootatoor Northwards, In all cases I found these, as described by 

 Mr. Blanford, similar in their lithological character, and having the same 

 relation of marked unconformity with the beds above, these beds being 

 then supposed to be of Neocomian age. Passing Northwards to Maravat- 

 toor, I found there beds of the same mineral aspect, and in these beds 

 remains of the same j)lants as were seen elsewhere. These beds had not 



* Cycadaceous wood, to the supposed occurrence of which in the Ootatoor beds 

 Mx. Blanford refers, has been found even in the older alluvium of this country. And 

 even assimiing the occurrence of the supposed Zamia fi-ond from Alundanapuram con- 

 fimied, it by no means follows that it was a Zamia of the same species a thase collected 

 from the plant beds. — T, Oldham. 



G 



