RECENT VOLCANOES, 287 



extra-peninsular region. But both to the west and east, volcanoes 

 appear in the two regions of curved ranges that join the great 

 Himalayan arc both at its eastern and western extremities. Among 

 the features common to the parts of those two regions that border 

 upon India, are the numerous parallel ranges made up largely of 

 marine tertiary strata, while in either case, the upper tertiary is 

 represented by rocks similar in age and appearance to the Siwaliks 

 of India. Mud volcanoes have long been known in either region, 

 and the existence of real volcanoes of recent and sub-recent date 

 must be added as a further connecting link. K6h-i-Sulta*n, Koh-i- 

 Tafda*n, Basman Koh, and the other volcanic centres of Eastern 

 Persia form the counterpart of Barren Island, Narcondam, Puppa 

 and other Burmese volcanoes. Nor is it only their geological age 

 that is similar, but the lavas of which they are built are identical. 

 The Burmese volcanoes also consist of andesites whose mineralogical 

 constitution is quite similar to the Eastern Persian ones : just as 

 in Eastern Persia, the presence of olivine is frequent, and the same 

 varieties of pyroxene and amphibole are met with ; a mineral very 

 similar to the peculiar red hornblende of Baluchistan and Persia 

 being very conspicuous in many of the lavas from Narcondam, where 

 it was noticed by Mr. Mallet, 1 and in the lavas of Puppa. 



1 Mem. Geol. Surv. Ind., Vol. XXI, p. 2S2. 



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