366 mil j. b. scrivj5nor on THE [June 1913, 



connexion between the rocks in these regions may he regarded as 

 probable on structural grounds ; but, in the case of all the countries 

 mentioned, nothing is needed so much as detailed palaeontological 

 research, which cannot be undertaken by geologists who are engaged 

 in economic work. The Dutch geologists are very little or no 

 better off in this respect than myself, if the comparatively greater 

 extent of the area with which they have to deal is considered. 

 The small collections of fossils obtained do but" serve to give a 

 rough notion of the geological horizons. 



There are two points, however, that I would mention. One is 

 the relation of the Eaub Series to beds some distance away to the 

 north. Dr. J. M. Maclaren, in his work on ' Gold ; its Geological 

 Occurrence & Geographical Distribution ' 1908 (p. 287), seems to 

 be of the opinion that the Eaub Series will, on examination, prove 

 to resemble closely certain limestones and shaly beds in the 

 Southern Shan States, described by Mr. C. S. Middlemiss, 1 which 

 have been referred to the horizon of the Middle Productus Beds. 

 I have not seen the limestones of the Southern Shan States, and 

 Dr. Maclaren, I believe, has not seen those of the liaub Series ; 

 but it may be that the prediction will prove correct, even if the 

 close resemblance is to include contemporaneity. The only way 

 to prove it, without very good palaeontological evidence, is to survey 

 the long stretch of country between the Southern Shan States and 

 the Peninsula. 



In the Northern Shan States the Napeng Beds are found lying 

 unconformably on limestone, or separated from it by faults." This 

 is suggestive of the relations between the Malayan Gondwana rocks 

 and the Eaub Series, and it would not be surprising to find that 

 the Napeng Beds have the same relation to the Gondwana rocks 

 of India as the Malayan rocks. The beds overlying the limestone 

 in the Southern Shan States, again, are described as being ' let 

 down by faulting ' or ' tucked in along certain lines and axes of 

 reversed folds and faults,' 3 but there docs not seem to he a close 

 resemblance petrologically to the Malayan Gondwana rocks. 



The limestones in Indo-China also, referred to the Permo- 

 Carboniferous, may ultimately prove to be part of the same forma- 

 tion as the Eaub Series (see p. 353). 



At present, the most important point to remember in this 

 connexion is that, taking the glacial horizon in Perak as being 

 equivalent to the Talchir and other contemporaneous late Palaeozoic 

 glacial deposits, the attempts to correlate the Eaub Series with the 

 Productus Beds of the Salt Eange on the scanty palaBontologieal 

 evidence 4 must be abandoned, unless we assume the series to be 

 contemporaneous with the shales underneath the boulder-bed in 



1 ' Report on a Geological Reconnaissance in Parts of the Southern Shan 

 States & Karenm' Gen. Rep. for 1899-1900, pp. 130 et seqq. (Geol. Sur,v. India, 

 1900). 



- M. Healey, ' Fauna of the Napeng Beds, &c.' Pal. Indica, n. s. vol. ii (1908) 

 Mem. 4, p. 1 (Mem. Geol. Surv. India). 



3 C. S. Middlemiss, op. supra cit. p. 143. 



4 See, for example, Geol. Mag. dec. 5, vol. iv (1907) pp. 565, 56G. 



