318 Transact Ions. — Geology. 



reports for mention of morainic beds that may be of red-gravel 

 age, but I have somewhere met with mention of " large 

 iingular blocks " in the drift of North Canterbury. The 

 glacier relics of one age are apt to be destroyed or obscured by 

 glaciers of a later and severer age — and there has been a 

 severer age ; but as there appears to have been a considerable 

 amount of seismic disturbance in the interval between the 

 two cold periods, moraines or other glacier beds of the earlier 

 or red-gravel period may here and there liave been lifted 

 above, or otherwise shifted out of the way of destruction. 



The total duration of the first cold age must have been 

 very gi-eat, to permit of the accumulation of so massive a re- 

 cord of the work of frost by streams having only small drain- 

 age-basins, and the duration must have been all the greater, 

 as the accmnulation was certainly not continuotis. Some of 

 the clays were evidently for long periods persistent land-sur- 

 faces ; in the Fairlie Creek dow ns there are two lignite-beds 

 in the formation, and, I am informed, in the Pareora downs 

 remnants of a forest or bush in petrified wood. I have not 

 yet given much attention in the field to the evidences of 

 variations of climate within tlie period, but, from what I have 

 seen, I think it likely that a good deal of evidence may be 

 obtained on this point. 



If we compare the red gravels of South Canterbury with 

 the later fans in the same localities, it is clear that the older 

 formation, as to bulk, is much the more important of the two. 

 This being so, we are compelled to ask, What has become of 

 the related larger masses which must have been laid down by 

 the larger rivers north of the Orari ? The reply must be that 

 they are buried under the later fans wdiicli form the surface of 

 the plains ; and I find in Haast's report, above quoted, some 

 facts recorded which tend to prove, not only that the Canter- 

 bury Plains belong to two periods, but that the greater portion 

 of the whole was laid down during the earlier period. In de- 

 scribing sections presented by vertical faces of the north bank 

 of the Rangitata, the report says (page 39) : '• T]ie shingle of 

 the Pleistocene fans shows an equal change from the natural 

 bluish tint to one of a rusty dark-yellowish colour, which coats 

 the whole deposit. I have found in several rivers that the 

 change from one colour to the other is often rapid, the dark- 

 yellow shingle underneath being divided from the Ijluish at the 

 summit by a very distinct line, sometimes with a small bed of 

 loam between them, over which, at numerous spots, small 

 watercourses are dripping down." Under the head of "Ash- 

 burton," page 40, Haast writes of terraces on the north bank, 

 in the broad valley of the river, and says : ''In some slips in 

 these terraces a distinct line of demarcation is visible between 

 the shingle and gravel of different colours, blue shingle in its 



