36 MIDDLEMISS: GEOLOGY OF HAZARA AND BLACK MOUNTAIN. 



of the Central Himalaya, only the protruding part is preserved in 

 most cases, the remainder, fixed in the rock, shewing no structure 

 when broken. Consequently as a rule all one could do in the way of 

 collecting was to break away the protruding parts. At one place; 

 however, the band had become softened into a loose sandy ferru- 

 ginous marl, and in this and the surface soil above Hira Lai and 

 myself were able to gather a rather nice suite of fossils. 



I have referred above to the sudden way in which the northern 

 type of Jurassics changes into the southern one. It is to be noticed 

 that the Cretaceous band is only found above the Gieumal sandstone 

 of the northern type, and that though continuous along the strike 

 direction for immense distances — right across Hazara in fact — in the 

 opposite direction, ue., to the south and south-south-east, it has the 

 same limited extension that the Spiti shales have, that is to say, it is 

 never found in the sequence above the southern type of Juras- 

 sics. 



I may here mention that the black band of the Spiti shales, and 

 the orange band of the Cretaceous, make two horizons of the greatest 

 practical use to the field-geologist. Although the country is rarely 

 so bare of vegetation as to shew the bed-rock when viewed from a 

 distance, still, both palseontologically and petrologically, they are 

 landmarks quite easy to follow in tracing out the complicated folds 

 and inversions of the strata. 



Waagen and Wynne, in their Memoir on Sirban hill, speaking of 

 the fossils of this stage say : — "They are chiefly 

 cephalopods, with a few gastropods ; one 

 Inoceramus has also been collected. The ammonites found belong 

 nearly all to the exclusively cretaceous groups of the Cristati and 

 Inflati; besides this several species of Ancyloceras, Anisoceras, and 

 Baculites appear. The Belemnites are numerous, and of rather 

 extraordinary size for their geological age. The impression which 

 the whole of the fossils leaves upon the observer is that of a ' Gault ' 

 fauna." 



The most common form of Ammonitidae that Hira Lai and 

 ( 36 ) 



