454 Transactions, — Geology. 



river, never filled up to the height of the plains at their reduced level, and, 

 on the laud being re-elevated, it remained as the river channel and was 

 gradually cut down into the gorge. 



There are several quite independent reasons for thinking that the sea 

 has flowed over the Canterbury Plains ; but these I need not repeat here as 

 they will be found in the Transactions of the New Zealand Institute, vol v., 

 p. 387, and in the Geological Eeports for 1873-74, pp. 5G-58. 



On the other hand two objections may be fairly raised to my hypothesis. 

 First, that there is no trace of flattened sea-shingle ; and second, that there 

 are no marine fossils. With regard to the first objectiou we must remember 

 that the form of beach shingle depends a good deal on the structure of the 

 rocks from which it has been derived, and that if the rocks have not a 

 schistose or slaty structure the shingle must remain for a considerable time 

 within reach of wave action before it can acquire a flattened form. This 

 objection may therefore be got over by supposing that subsidence and re- 

 elevation were continuous and tolerably rapid. The second objection rests 

 only on negative evidence as no fossils of any kind have been found. It is 

 of no value here where the beds, except quite the upper portions, are allowed 

 to be of fluviatile origin, and are composed of shingle through which water 

 easily percolates ; for under these circumstauces all calcareous remains are 

 soon dissolved. I think, therefore, that the objections to the hypothesis 

 here put forward are of far less weight than the objections to any other 

 hyphothesis ; but, whatever value may be attached to the argument, it is 

 certain that no theory of the formation of the Canterbury Plains can be 

 satisfactory if it fails to account for the lower gorge of the Waimakariri. 



Art. L1I. — Recent Discoveries in the Neighbourhood of Milford. Sound. 

 By Donald Sutherland. Communicated by Alexander McKay. 

 [Read before the Wellington Philosophical Society, 15th August, 1884.] 

 Plate XLII. 

 Messrs. Sutherland and McKay, well known as explorers and prospectors 

 of Western Otago, have for some years past devoted their attention to the 

 vicinity of Milford Sound, and from their principal camp at the head of that 

 Sound, they have explored the country in almost every direction. Sur- 

 rounded as Milford Sound is by impassable mountains to the east and north, 

 the valley of the Arthur Eiver lying southward of the head of the Sound 

 presents the only hopeful route by which to reach the Lake District of 

 Otago. The eastern branch of the Arthur Eiver, above Lake Abraham, was 

 explored to its source, but no outlet was discovered in this direction, the 



