CRETACEOUS SERIES. 27 



think must be near the very base of this bottom sandstone : just 

 above the short and narrow gorge by which the river cuts across the 

 massive sandstone it takes a sharp turn from the west^ and soon again 

 makes a wide sweep from the north-west. This wide bend of the 

 river takes place against chffs of the sandstone, and there is still a rem- 

 nant of this rock on the inner side of the curve on the left bank, and 

 here the fossil bed occurs at the low-water mark. Just above this bend 

 the trap shows again on both banks forming sheer cliffs of 100 to 200 

 feet in height. Unless some undetected dislocation exists, this fossil bed 

 must be close to the very base of the series. It is a friable rusty 

 sandstone, and is the lowest bed, except the coaly layers, in which I 

 foimd fossils; there are Brachiopods, Echini, and very numerous pieces 

 of large Inocerami. In connection with the foregoing discussion re- 

 garding the true equivalence of the bottom rock throughout the whole 

 area it is very interesting to observe that fragments of fossil resin are 

 freely scattered among the marine fossils in this bed ; and are pro- 

 bably derived from the same source as that found in the coal of the 

 bottom beds at the higher level. 



Over a portion of the cretaceous area on the plateau there are two 

 recognisable sub -divisions of the series between the Cherra band and 

 the bottom rock. Immediately below the former, and sometimes, as 

 we have seen, with a sharply defined boundary, there is a group the 

 characteristic rock of which is a very fine pale sandstone with very 

 numerous scattered small broken fragments of plants, generally coated 

 with dark brown or black. Everywhere with this sandstone a calca- 

 reous ingredient is associated, but in a strangely capricious manner : 

 of two closely adjoining sections one may be strongly calcareous through- 

 out and the other almost quite free from any such admixture. This 

 is the case on two of the paths from Cherra Station down to Nongpriong. 

 Generally the Kme is accumulated in discontinuous layers, thick or thin, 

 forming calcareous sandstone and every degree of sandy limestone. In the 



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