1867.] HAAST CANTEEBUKT, NEW ZEALAND. 351 



slates which constitute the isolated low wooded cones or ridges 

 rising at present above the morainic accumnlations, suggests at once 

 that the whole country was uniformly covered with one continuous 

 sheet of ice, grinding and planing down the whole lower region in a 

 remarkable degree. And, if we go further, may we not assume 

 that the enormous triturating power by which the auriferous beds 

 were ground down to nearly their present outline, may in some 

 degree account for the presence of the fine dust-like gold found in 

 large quantities along the shores of that coast for several hundreds 

 of miles ? 



The older alluvial beds, lying, in several instances, upon these 

 morainic accumulations, show convincingly, when their contents are 

 examined, that at the time they were deposited a great change in 

 the relative position of the Alpine glaciers had taken place. 



Although many rolled boulders from the very summit of the cen- 

 tral chain may still be coUected amongst them, derived either from 

 the younger moraines of the smaller glaciers, or from the older 

 moraines through which their outlet had cut a passage, we find that 

 the metamorphic schists and gneiss >^ granite of the Southern Alps 

 proper, and the newer granites and syenites of the hills in front, 

 are also well represented. Such a total change in the nature of the 

 beds proves convincingly that the glaciers have not only retreated 

 considerably, but have now formed distinct channels on the lower 

 slopes of our Alps, the streams issuing from them being able to bring 

 down the debris from the granite bosses in front. 



These Postpliocene river-beds, of such distinct lithological cha- 

 racter, mostly repose upon, or occur near the moraines. But 

 there is one instance, in Boldhead, which at first sight seems to in- 

 dicate that at least one oscillation occurred during the glacier-epoch, 

 during which the Boldhead glacier must have retreated so consider- 

 ably as to bring the lower metamorphic and hypogene rocks within 

 the denuding action of its outlet. These interesting fluviatile de- 

 posits consist of beds of sedimentary and semimetamorphic rocks, 

 which form the morainic accumulations of well-rounded boulders of 

 granite, gneiss, and metamorphic schists, which, during the great 

 glaciation of the country, were covered uniformly by a sheet of ice. 

 In fact, these Postpliocene fluviatile beds cannot be distinguished 

 from the present river-beds of the same region, except by the some- 

 what larger size of their blocks of stone. 



At first sight it thus appears that such a considerable change has 

 taken place during the glacial epoch that the Boldhead glacier could 

 retreat at least ten miles, so as to uncover the coast-ranges, which, 

 although in that neighbourhood from 3000 to 4000 feet high, have 

 the peculiar rounded forms of true roches-moutonnees. But as signs 

 of such enormous oscilLations are nowhere else discernible, a second 

 explanation may be more correct — namely that the alluvial river- 

 beds were deposited by the river Mikonui, which enters the sea a 

 few miles north, during a slight oscillation of the Boldhead glacier. 

 There occur also in Boldhead, and in some other cliff's further south, 

 very large deposits, consisting of the finest glacier-mud, which are 



