58 



carboniferous period as Mr. Johnston surmises, but the 

 boulders and pebbles in the recent moraines north of Lake 

 Margaret and on the Linda Company's ground at Mount 

 Lyell cannot be confounded with the ancient conglomerates, 

 for the scored boulders are all of local origin, differing in 

 character and form from the rocks of the ancient conglo- 

 merate ; the scorings are also much deeper and decided in 

 appearance. If parts of the older conglomerate had been, 

 disintegrated from the parent mass and become mixed with 

 the recent morainal matter, the scorings would have been 

 obliterated, for the best specimens from the ancient beds, 

 bearing the deepest ice marks, are in rocks of a soft nature, 

 though some of the harder ones are marked with very fine 

 scratches. 



Mr. Montgomery in his able paper read last year, entitled 

 " Glacial Action in Tasmania," remarks that I state Mounts 

 Sedgwick and Dundas are capped with greenstone ; he adds 

 to these Barn Bluff, Mount Pelion, Mount Qssa, the Ducane 

 Bange, the Bldon Bange, East Mount Pelion, and the Oakley 

 Bange as showing the same feature. The additions compose 

 part of the great greenstone plateau of the centre of the 

 island, or I should say a long offshoot of the same, dividing 

 the waters of the northern and western rivers. This high 

 dividing chain of mountains should not be confounded with, 

 the West Coast Bange with its two isolated peaks of green- 

 stone, Mounts Dundas and Sedgwick ; except these and the 

 schistose summits of Mounts Bead and Darwin, all other 

 eminences in the West Coast Bange are capped with a 

 quartzose conglomerate. In my paper I noted the peculiarity 

 of these greenstone peaks as differing from the formations on 

 the other heights of the range. 



Mr. Montgomery found in his additions the columnar 

 greenstone resting on the coal measures, which is a noticeable 

 feature on the great greenstone plateau further south from, 

 his explorations, and surmises what he terms the moraine at 

 Mount Sedgwick to be coal measures similarly situated. As 

 we once visited Mount Dundas together, Mr. Montgomery is 

 aware that this feature is not seen there, and when he has 

 leisure to examine Mount Sedgwick, I do not think he will 

 conclude that the greenstone rests on the ancient glacial 

 conglomerate, but he will find rounded detached masses of the 

 conglomerate resting on a porphyretic spur on the western 

 side of the mountain, which have been disentegrated from the 

 parent bed situated on the south-east side, and probably 

 carried to their present resting places during the recent glacial: 

 epoch. He adds, " I cannot think it at all probable that Mr. 

 Moore is correct in referring the conglomerate containing 

 fossils to the action of floating ice. It seems more likely that 

 it is a moraine drift derived from the lower beds of the 



