32 



LA TOUCHE : GEOLOGY OF NORTHERN SHAN STATES. 



In compiling this list I have thought it advisable not to adopt 



Nomenclature c ^ ass ^fi cat i° n °f ^ ne systems proposed by Sir 



T. Holland in the Summary of Indian Geology 

 published in the latest edition of the Imperial Gazetteer of India 

 (Vol. I, Chap. II). 1 



That classification is intended to apply to the peculiar conditions 

 existing in the Indian Peninsula and the Himalaya ; where, as 

 Sir T. Holland explains (Op. cit. p. 10), the chief post-Archaean 

 breaks do not correspond to those on which the European nomen- 

 clature is founded. Thus the only break of first importance in 

 the sequence of fossiliferous rocks in India, separating the Dravi- 

 dian from the Aryan Group, took place at about the Permo-Car- 

 boniferous stage, when " there was a pronounced revolution in the 

 physical features of the Indian area." In the Shan States, on the 

 contrary, deposition was more or less continuous from lower Or- 

 dovician times to the close of the Permo-Carboniferous stage, when 

 a great interruption occurred corresponding to that between the 

 Palaeozoic and Mesozoic periods in Europe. Indeed, it was even 

 more pronounced in the area now described, for the whole of the 

 Trias, unless we include the Rhaetic with that system, is not re- 

 presented at all. There seems, therefore, to be no need in the pre- 

 sent instance to depart from the nomenclature that has been well 

 established by common usage. 



1 Simla, Government Central Printing Office, 1904. 



