30 MALLET: GEOLOGY OF DARJILING AND WESTERN DUARS. 



and strongly contrasting ironstone shales, would not be easy : it is, 

 however, more likely that only one group is represented. The fossils as 

 yet found in the Darjiling rocks comprise Glossopteris of two species (one 

 of which is Browniana, the other undetermined) , Vertebraria, FTiyllolheca 

 and Trizygia (Annularia) . Of these, all, except the last, are common in 

 both groups as typically developed, whilst Trizygia has only been found 

 in the Raniganj. It is, however, so rare even in these beds, that Mr. 

 Blanford* does not seem to consider its not having been yet found in the 

 Barakars as conclusive evidence of its non-existence there. Further, 

 Dr. Hooker's observation of Trizygia in the Darjiling beds, which he 

 himself speaks of doubtfully, has not been since confirmed. At the same 

 time there is a " plant allied to Sckizoneura/' abundant and generally 

 distributed through the Raniganj group * of the type field, that has 

 not been as yet observed in the beds in question ; but the fossil collections 

 made are too small to allow of satisfactory inferences from this fact. 



The lithology of the Darjiling beds seems to approximate in some 

 respects to that of the Raniganj group. Mr. Blanford says of the 

 latter, that " the sandstones are generally finer in texture, and are massed 

 in beds of greater thickness, than those below the ironstones ; the coarse, 

 white, felspathic sandstone and conglomerates are almost entirely 

 wanting. Nodular hard calcareous bands are frequent ; the coal is more 

 regular, of more even quality, and not so frequently a mixture of coal 

 and shale, and the seams have a uniform thickness over considerable 

 areas. Pebbles are scarcely ever seen ; shales are common." f In the 

 Darjiling beds, the sandstones, as a rule, are rather fine-grained ; they 

 sometimes occur in thick masses, and coarse, white, felspathic sandstones of 

 the Barakar type are not common ; they are not unfrequently somewhat 

 calcareous, and conglomerates are absent. No comparison can be made 



between the coal-seams in the two localities, owing to the crushed state of 



% 



* Vol. Ill, pt. 1, p. 44. 

 f Ibid, p. 10. 



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