J9I-'.] STEVENSON— THE FORMATION OF COAL BEDS. 539 



sidence began, the area was diversified with hills and valleys, now 

 reduced to a common level by the mud deposit. One is not justified 

 in referring to the evidence respecting the peat accumulations as 

 unimportant ; the observations embrace an area greater than that 

 of all the coal basins within central France. 



But similar conditions exist elsewhere on the India peninsula. 

 Medlicott^^'' published with comments the notes made by G. E. 

 Ormiston during excavations for a government dock on Bombay 

 island, on the west coast of India. In a space of about 30 acres, 382 

 trees and stumps were uncovered, of which 223 were erect. Some 

 of the prostrate stems were without roots, but others had been over- 

 thrown in place, for the roots were still partly embedded in the 

 soil. The stumps are rooted in a thin soil of decomposed basalt and 

 are surrounded by a stifif blue clay on which rests black marine mud, 

 4 to 5 feet thick. Stumps projecting above the clay into the black 

 mud have been drilled by Teredo; in some cases the holes pass 

 downward through the trunk towards the roots and are filled with 

 indurated clay. Medlicott states that the trees are Acacia catechu; 

 two drifted logs of teak wood were found in the clay. This clay 

 deposit must have been made very quietly, for a prostrate stem shows 

 its branches and even delicate twigs in place. The soil was very 

 thin and the roots spread out horizontally; the trees were large, 

 one of the prostrate trunks being 46 feet long. How far the forest 

 extends is unknown, as no investigations were made beyond the exca- 

 vation of 30 acres. 



But while the region of the Ganges and Indus have been sub- 

 siding more or less since the late Tertiary, there have been local 

 elevations of no mean extent within recent time; and their charac- 

 ter is such as to leave no room for doubting that they had many 

 predecessors. Fergusson^^' notes the comparatively recent elevation 

 of the Madorpora Jungh, at whose southern extremity the city of 

 Dacca was built. This uplifted area is 75 miles long with an extreme 

 width of 35 miles and a height of 100 feet on the west side toward 

 the Brahmapootra. Fergusson describes in detail the shiftings of 



"* Records Geol. Surv. of India, Vol. XIV., 1881, pp. 320-323. 

 '^ J. Fergusson, "On Recent Changes in the Delta of the Ganges," Quart. 

 Journ. Geol. Soc, Vol. XIX., 1863, pp. 329, 333-350. 



