116 Notes on Geological Specimens from [Feb. 



trees, sometimes hollow, and always in concentric rings of deposit, 

 forms a beautiful sight when in masses of several tons weight. The 

 strata were seen in one place to be 12 feet thick, and to rest on the 

 common black alluvial soil ; near this, it had filled the original bed of 

 the stream, and forced it to find another channel : and in two places, a 

 fall of three or four feet, forming a pretty cascade, seemed to be occa- 

 sioned by the growth of the rock, and the wearing away of the channel 

 below. The deposit often conceals the remains of plants, with a smooth 

 coating of considerable thickness and firmness, frequently rounded in 

 irregular sections of large circles ; in others, in nodulous forms of great 

 beauty, covering over the extremities of the smaller or larger branches, 

 and occasionally preserving the wood in an hermetically- sealed cavity. 

 The roots of the Banian now and then pass into the empty tubes, as 

 if they were the mould on which they are formed ; others probably 

 form on the weeds, which flourish in the wildest luxuriance along the 

 banks : one of these I found to be 24 feet in height. Recent shells, 

 such as now inhabit the stream, were found in many places enveloped in 

 the stone. One fine specimen of lymnaa was attached to the side of 

 the rock, as if it had been arrested there by the deposit of stone around 

 it, and which has taken its shape ; its fine surface, where it adhered, 

 being that of the fresh shell ; while the coating exhibited the color and 

 fracture of the tuffa of the hillocks south of the Payngunga, and others 

 exactly similar, near the town of Kair. Roots and branches were 

 seen to lie in the deep water without a coating of stone ; but the series 

 of observations so accurately described by Mr. Lyell was completed, 

 by finding where the stream fell over some rocks, a plant still living, 

 whose roots were thickly interwoven, and the leaves on a level, and just 

 above the water, cemented into a mass of firm white tuffa. (Specimens 

 of the water and tuffa were formerly sent.) 



The spray seemed, therefore, to produce the deposit more quickly ; 

 but specimens of moss growing below the water were also converted 

 into sharp brittle spiculse. 



Below, some blocks were softened, and as if in part redissolved. 

 Amongst the petrified plants, one tree 1^ foot in diameter was seen : 

 and also a few leaves ; but these were rare, I suppose from their rapid 

 decay and smooth surface ; one of them seemed to belong to a species 

 of lotus seen in a pool above, and another seemed to be the leaf of aloe. 

 In some places the tuffa was sandy, and in one or two slightly tinged 

 with iron ; some of it had a fine crystalline appearance, and considerable 

 hardness ; while other specimens could not be distinguished from kun- 

 kar. A tendency to the formation of a bluish white scum was observed 

 on the surface of the still water, both here and at Lingtee : a slight 



