X, A, 3 Smith: Reconnaissance of Mountain Province 199 



Lubuagan and Sician, in the sandy shale portions of what must 

 be the same series, I found the following forms : 



Turbo borneensis Bttgr. (?). Cassidaria sp. 



Pecten senatorius K. Mart. Tapes sp. 



Pecten leopardus K. Mart. Dosinia sp. 



Cardium sp. Turbinella tjidamarensis K. Mart. 



Conus sp. Fragments of Alcyonaria. 



Cycloseris decipiens K. Mart. 



The presence of these fossils stamp this formation as Mio- 

 Pliocene. 



Shales. — The shales which are found intercalated in the sand- 

 stones of this region grade imperceptibly into them. Mineral- 

 ogically they are the same and differ merely in grain size. Plate 

 V, fig. 1, gives an excellent idea of their field occurrence. The 

 thickness of these beds would in the aggregate amount to from 

 300 to 600 meters. The repeated alternation of sandy and shaly 

 layers in practically all of the sections, but particularly in this 

 one, indicates that these beds were laid down in shallow water. 



The cliff shown in the photograph is one of the most dangerous 

 on the trail between Bontoc and Lubuagan, due to the crumbling 

 nature of the beds, together with the inclination, which is approx- 

 imately 45°. No fossils have been found here. 



The conglomerate. — I have alluded already to a local conglom- 

 erate associated with the limestone at Sagada, but the one I 

 shall refer to now is the basal conglomerate equivalent to the 

 "Agno beds" of von Drasche. It does not appear to be developed 

 to the extent of the beds in the type locality on Agno River 

 or along Bued River. This formation is mineralogically the same 

 as the sandstone and the shale, the difference again being one of 

 grain size. Naturally we find andesitic and dioritic material 

 predominating, as these rocks predominated in the ancient head- 

 lands of the Tertiary seas. It is very easy to confuse some of 

 the conglomerates with the volcanic agglomerates. Also the 

 sandstones, in places, through concentric weathering, simulate 

 the conglomerates. I have no idea at present of the thickness 

 or extent of these conglomerates. 



Sinter. — In this region hot springs are occasionally found 

 where great quantities of siliceous and calcareous sinter are to 

 be seen. At Salinas, in Asin Valley, one finds the best and 

 most beautiful deposits (Plate V, fig. 2). At Mainit, near 

 Bontoc, there are terraces, but the Balotoc hot spring deposits 

 practically no sinter. 



Travertine. — We cannot omit from a complete list of sedimen- 

 taries the ubiquitous deposits of travertine here and there in the 



