THE PATLI D6N. 75 



of fossils, if fossils ever existed in them. On that supposition, there- 

 fore, how does it happen that the agents of metamorphism have 

 worked over such great areas, and left such extraordinary linear 

 oases of nummulite-bearing rocks near the outer margin of the hills ? 

 If we assume the metamorphism to be of the nature of all known 

 metamorphism, that is to say, either regional or due to intrusions of 

 igneous rocks, we cannot believe, considering the wide extent of 

 country which has been metamorphosed, that any action of such 

 nature would be able to cease along such abrupt lines as the neces- 

 sities of the case would demand if the fossiliferous strata were only 

 slightly altered portions of the same series. If, on the other hand, the 

 schists be regarded not as metamorphic but as primitive (in a sense), 

 the distinctness of the nummulitics needs no comment. 



Perhaps I may be deemed to be exerting myself unnecessarily to 

 demolish what may be thought by the reader to be an unwarranted 

 belief ; but from my own past experience I know how apt the mind is 

 to neglect these larger and indirect results of reasoning over wide 

 areas in favour of a local section showing an apparent passage. For 

 instance, in the Pelini R. the lie of the two sets of strata is exceed- 

 ingly similar. Through the zone of purple slates there stand out from 

 the shingle of the river-bed, long, low quays of the thinly bedded rock 

 with an almost vertical dip. Through the nummulitic zone identical 

 quays of a thinly bedded rock with a high dip seem so palpably a 

 continuation of those slates that the keenest geologist, if by chance 

 he missed the fossil-bearing bands, would map them all as one. 



But I have shown that, if our knowledge of the laws and condi- 

 tions of metamorphism be not entirely a myth, this cannot be the case. 

 The nummulitics, therefore, must be newer than the slates and schists, 

 and therefore there must be a fault separating them from these rocks. 

 Thus, in the Pelcini R. section we have to place a fold-fault on the 

 north side of the nummulitic band of strata, of at least 4,500 feet 

 vertical throw ; for the fault once being granted, there is then no 

 reason for referring the purple slate and breccia series to any other 

 horizon than one below the massive limestone, in conformity with 



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