1850.] Report on the Valley of Spiti. 435 



belong to the " Porkilitic" group, being situated between the beds of 

 " lower new red sandstone" and the Magnesian group or dolomitic 

 conglomerate ; these again being associated with beds of shale, and 

 mountain lime-stone, point it out as an exceedingly likely locality for 

 coal ; the snow however was on the ground and the Thermometer not 

 above 10° in the middle of the day, when I visited the place, so that 

 my observations were unsatisfactory. 



The fossil beds of Ammonites are of great extent, varying from the 

 size of a cart wheel, to an inch in diameter : in a very short time I 

 collected as many as two men could carry, and could distinguish as 

 many as six or seven different species of Ammonite, with a variety of 

 other shells, and one or two vertebrae of fish. 



Oxide of Iron. — A large quantity of red oxide of iron is found 

 somewhere in the vicinity, which is used by the people for ornamenting 

 their houses, marking their sheep, &c. ; this locality, when free from 

 snow, would be worth observing, because beds of this description often 

 overlay silver and lead ores. 



Lias and lower Oolitic beds. — The other fossil beds, which I exa- 

 mined, are in one of the lateral valleys near the village of " Gienmul." 

 The formation corresponds with our well known " Lias," and " lower 

 oolitic" reposing on the Lias. The mountain, behind which these 

 beds are situated, is composed of a series of calcareous and sandstone 

 beds, in an almost undisturbed position. 



The decomposing Lias, with much indurated mud or clay, and greatly 

 tinged with iron, have greatly the appearance of a coal field, and are 

 on undulating hills; these are filled with ammonites of only one 

 species : the decomposition of this group furnishes the richest ground 

 in Spiti ; the soil at " Lidang" and " Lara" seems also to be of this 

 description, but the fossils are not so abundant. The lower oolitic 

 reposes on the Lias, and is composed of rather complicated strata, 

 containing immense quantities of dead shells in a black deposit of 

 extreme fineness ; this clay is perhaps an indication of the neighbour- 

 hood of coal. I procured a quantity of these fossils, consisting of a va- 

 riety of bivalve shells, one or two univalves, and varieties of Belemnites 

 and " Orthoceras." 



The mountain lime-stone is the most abundant formation in Spiti, 

 and abounds with species of ammonite, Orthoceras, Spirifer, Ters- 



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