22 GEOLOGY OF CUTCTI. 



of rocks of the same general character as those descrihed lias, in Southern 

 India, been traced from the Trichinopoly district northwards for more than 

 five degrees of latitude. These rocks invariably occur in small isolated 

 patches, all but denuded away, and resting on the uneven surface of the 

 old- crystalline gneiss and other metamorphic rocks. Their identity can 

 in almost every case be established not only by the strikingly constant 

 mineral chai-acter which they present, but also by the almost invariable 

 presence of plant remains of several species, clearly identical wdth those 

 in the typical Rajmahal beds. Every thing, therefore, has tended to 

 establish the conclusion arrived at in 1859, that these South Indian beds 

 were unquestionably of the same geological age as the Rajmahal group. 

 And, if this be established by the researches in Cutch to be lower Jurassic, 

 the Madras Palseozamia-beds must be admitted to be of this age also. 



As I have just 'stated, this has not yet been definitely ascertained; 

 all ihat is proved is, that they are not older than this. Captain Grant 

 originaU}^ thought them representatives of the oolitic coal of Yorkshire. 

 Morris, when fa*st describing thesis Paljeozamia, pointed out the great 

 interest attaching to them from their striking analogy with Stonesfield- 

 slate fossils. D'Archiac (Hist. deg. prog, a. 1 Geologic, VII, 624) pointed 

 out the confusion in Captain Grant^s desijtiption, but accepting his state- 

 ments referred the plant-bearing beds to the horizon of the ' lower sand- 

 stone and shale ' of Phillips'* divisions of the oolite, and the same lower 

 Jurassic age has been accepted as established by several subseqiient writers. 

 It is not improbable that further research may fully establish this con- 

 clusion. But there are several curious anomalies in the flora of this 

 Eajmahal series which prevents my admitting this age as established up 

 to the present. I should prefer leaving the point open, admitting only 

 this general conclusion, that the Rajmahal series of Indian Geology must 

 lie between the bottom of the cretaceous system and ( ? the top of) 

 the lower Jurassic group. 



T. OLDHAM. 



Fehmary, 1867. 

 ( 38 ) 



