521 



Some Memoranda on the Geology of Sikkim. Communicated 

 by D. L1STON5 Esq. 



[With a Sketch Map of the Country, Plate XXXV.] 



The portion of Sikkim visited by me in company with 

 Capt. B. is bounded on the east by the river Teesta; on the 

 north by the Kuilait; on the east and north by the great Run- 

 geet ; and on the south by the Morung or Terai. DarjeeUng 

 I first approached from the plains by the new road along 

 Sinchul^ and had occasion to travel that course several times ; 

 once also we proceeded from Punkabaree to Darjeeling by the 

 valleys of the Bellassun and smaller Rungeet, and returned 

 by the same path to Kursiong. From Kursiong we on one 

 occasion proceeded to Punkabaree by the left side of the 

 Bellassun. We travelled down the great Rungeet, Teesta and 

 Jubbon rivers to the plains. We likewise sought the sources 

 of the Mahannudee under Mahaldaram from Kursiong^ and 

 returned to Darjeeling round the shoulder of Sinchul, crossing 

 the Rungoong at Sengenboom^ and ascending by Ging to 

 Darjeeling. We also ascended the valley of the great Rungeet, 

 crossing the Rumam, Rutto and Reshee rivers to the KuUait, 

 and proceeded up the Kuilait three or four marches. I left 

 Capt. B. at Hee, a Limboo settlement on that river ; he per- 

 severed in making an attempt to reach the snow, though pre- 

 vented from attaining his object by the jealousy of the 

 people ; while I returned to Darjeeling by a little frequented 

 path, which skirts the sources of the Reshee and Ruttoo, and 

 crosses the valleys of the Rumam and small Rungeet. Thus 

 I had good opportunities of seeing the country, and if I make 

 but an imperfect report of its geological appearance, the cause 

 lies rather in my want of qualification to make proper use of 

 my advantages, than from my not having possessed occasions 

 which I might have availed myself of with profit. 



The general result of my observations is, that the higher 

 ridges are composed of gneiss rock, but round their sides is to 



