168 LA TOUCHE: GEOLOGY OF NORTHERN SHAN STATES. 



valley, there is almost impenetrable jungle, and the only traces of 

 the presence of the Zebingyi beds at the base of the limestone 

 are fragments of the black shales with Tcntarulites elegans, which 

 may be picked up in the talus. They have not been detected on 

 the north side of the Sedaw valley, where there is an outlier of 

 the overlying limestone. 



The grapto'ite beds are exposed in several places near the crest 

 of the ridge east of the Zebingyi plateau, 



Crest of Pyintha ridge. , ° , ■ ^^ 



tormmg a narrow band running roughly 

 parallel to the cart road from Pyintha northwards. A poor ex- 

 posure is seen in a water-course close to the crest of the ridge 

 about a mile south-west of the village, but a better one occurs in 

 the stream that crosses the road at the village, and about half a mile 

 above the crossing (Loc. 44, B 5). The beds here consist of shaly 

 black limestones dipping E. 20° N. at about 18 degrees, and contain 

 Tent, elegans and graptolites in large numbers. The latter 

 are in a rather better state of preservation than at Zebingyi, 

 and besides Monograptus dubius another species, M. cf. riccarton- 

 ensis Lapworth, occurs, a species characteristic of one of the zones 

 in the Wenlock beds of the Welsh borderland. The outcrop ex- 

 tends for some two or three hundred yards along the stream bed, 

 and at the lower end of it some rotten argillaceous rocks were 

 found containing trilobite fragments, probably of Phacops slian- 

 ensis, but too soft and friable to be worth carrying away. 



The black limestones crop out on the cart road itself just be- 

 yond the 29th mile, and then follow the 



Extension northwards. . ,, ... .,, . 



crest of the ridge to withm a short distance 

 south of Kyinganaing, crossing the road again at the 32nd mile 

 (Loc. 43, 5). Here the black limestones have disappeared, 

 and the beds are very soft, pink and lilac coloured clays, but 

 containing enormous numbers of Tent, elegans, crowded together 

 on the bedding planes in the utmost profusion. Fifty or more 

 can freauently be counted, according to Mr. Cowper Reed, in an 

 area of 20 sq. mm. A mile further on the band, in the same clayey 

 condition, crosses the road a third time, and then rims diagonally 

 across the slopes towards Thondaung station. 



At this locality (Waboye of Mr. Cowper Heed's Memoir), the 



o , Zebingyi beds are exposed in two places. 



Section at Lbondaung o- 7 * r 



(Fig. 5). A poor outcrop of the black shales with Tent. 



