48 HAYDEN; GEOLOGY OF THE PROVINCES OF TSANG AND 0. 
From the base of the second limestone upwards fossils are 
fairly numerous, and when the collections made have been worked out it 
will no doubt be possible to recognise at least some of the European 
horizons, and perhaps even to define their approximate limits. At 
present, however, the Rtidista; of the second limestone have not been 
determined and may be either turonian or senonian species — possibly 
both stages are represented. 
The age of the third limestone appears to be at any rate partly 
senonian, since it is overlain by beds with typical maestrichtian 
fossils, such as Plicatula hirsnta Coq., Cyclolites regularis Leym., 
Orbitolites macropora Defr. and species of Hemipneiistes, all of 
which forcibly recall the maestrichtian beds of Baluchistan (see 
Pal. Ind., ser. XVI, Vol. I, pt. 3). 
The absence of determinable fossils from the ferruginous sand- 
stone and the beds immediately below it make it impossible to define 
the upper boundary of the Cretaceous system, but it seems hardly 
likely to lie below the base of the sandstone and may possibly be 
above it : there is no sign of the unconformity which is so frequently 
found at the base of the Tertiary system in India. 
The only area not yet referred to, in which rocks believed to be 
of Cretaceous age were seen is the immediate neighbourhood of 
Lhasa. The prevailing rock on the right side of the Kyi Chu from 
Lhasa to Troiung is granite, but along the lower slopes of the hills 
there are dark shales overlain by limestone. On the spur running out 
into the Lhasa plain beside Nechung, the temple of the Oracle, a 
series of limestone and slate dips into the hill against the granite of the 
main ridge ; all the beds are much altered by the granite, but traces 
of fossils, apparently including echinoids, were seen in the limestone. 
For several miles below Drepung the lower spurs are composed 
chiefly of limestone, and near Gang-gi-ri, where a gigantic figure of 
Buddha has been carved on the face of a limestone cliff, some of the 
beds are distinctly fossiliferous. Unfortunately the fossils are merely 
represented by sections of what appear to be lamellibranchs and in 
some cases resemble sections of Radiglites, but neither here nor pa the 
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