262 LA TOUCHE : GEOLOGY OF NORTHERN SHAN STATES. 



Similar masses were also found across the Nam-La wng on the 

 crests of the ridges about Man-pung, (I 3) and again still further 

 east on a ridge to the south-west of Man Hpai (I 4), where bryo- 

 zoa are fairly numerous. Finally, a band of reddish limestone, 

 crowded with Fusulina elongata, resembling the Fusulina band at 

 Kehsi Mansam, was discovered by Mr. Coggin Brown at the Natural 

 Bridge on the Nam Lan river, one of the southern tributaries of 

 the Nam-Tu, near Nanio (F 4). Here the Fusulina band rests on 

 the ordinary Plateau Limestone, and is succeeded above by red 

 shales belonging to the Namyau series, faulted against the Plateau 

 Limestone as at Kehsi Mansam. 



On examining thin sections of the limestones collected in the Shan 

 States under the microscope, I have found that cer- 



Limestones of doubt- ^ ^ limest(me8 which J tad thought, from 

 lu I age. ' o ' 



their apparent position in the field, should be 

 included with the next overlying group, the Rhsetic or Napeng 

 beds, contain poorly preserved fragments of a Fusulina, not specifically 

 determinable, but differing in shape and in the internal arrange- 

 ment of the cells from F. elongata. These 



Section at Htengnoi. ,. .. . . . . . . ~ T , 



limestones are exposed m the bed. of the JNam- 

 Tu at Htengnoi (F 3), and the beds were traced for two or three 

 miles to the north of that place towards Nawnghkio. They are 

 well seen in the bed of the river above Htengnoi, where they dip 

 to the E. or S.E. at angles of 20 to 30 degrees. They extend 

 for about half a mile up the river, and are apparently succeeded 

 below by thick beds of conglomerate, which in turn rest upon 

 steeply inclined beds of the massive Plateau Limestone. It was on 

 account of these conglomerates, which contain well rolled pebbles of 

 the Plateau Limestone, that I mapped the blue limestones as belonging 

 to the Napeng beds ; but as they are now found to contain Fus- 

 ulina they are probably older. As usual the section is incomplete, 

 and the conglomerates are not actually seen to underlie the blue 

 limestones, but occur in detached masses which may have been 

 let down from a higher level by the solution of the limestone 

 beneath. Further exploration of the neighbourhood is necessary 

 before the relations of the rocks in this interesting section can be 

 made out. 



The peculiar oolitic limestone, a section of which is shown in 

 Plate 15, fig. 1, occurs lower down the valley near the village of 

 Na-aw, and appears to be near the horizon of the Fusulina beds of 



