236 GLACIAL ACTION IN AUSTRALASIA. 



has been entirely filled up, the moraine rising to about 100ft. above 

 the old lake deposits.* 



Canterbury. — We now pass over a space of about fifty miles in 

 length in which no ice-marks have been described, although no 

 doubt they exist, and come to the group of mountains which give 

 rise to the Waimakiriri on the east and south and to the Teremakau 

 on the north and west. 



The ancient glacier of the Waimakiriri was thought by Sir J. 

 von Haast to have extended for a length of fifty-four miles, reach- 

 ing as far as the middle portion of the Malvern Hills. But in the 

 valley itself there appear to be no glacier-marks below the junction 

 of the Broken River, neither are there any in the valley of the 

 latter, and it is probable that the morainic accumulations at Little 

 Racecourse Hill and at the junction of the Kowhai with the Wai- 

 makiriri may have been brought about by a glacier coming down, 

 the Kowhai Valley and fed from the slopes of Movmt Torlesse and 

 Big Ben. Lakes Grasmere, Sarah, Letitia, and Blackwater are 

 remnants of old glacier lakes now almost entirely filled up.f 



In the valley of the Rakaia the ancient glacier-marks are 

 clearer than in any other part of New Zealand which I have 

 visited, the lateral moraines on the sides of the hills being specially 

 noticeable. It appears to be pretty certahi that this glacier, at the 

 time of its greatest extension, debouched on to the Canterbury 

 Plains, and that we have in Woolshed Hill a remnant of its 

 terminal moi-aine.;}: Lake Coleridge is an excellent example of a 

 rock basin formerly covered by ice. as it has no morainic accmnu- 

 lations at the lower end. It will be difficult to explain the origin 

 of this rock basin except on the theory that it avus excavated by 

 the ice. A large lake formerly existed in the Rakaia Valley above 

 the gorge, but it has been filled up a long time. The reason why 

 Lake Coleridge still remains is that it lies outside that part of the 

 valley occupied by the Rakaia, and that it drains back into the 

 Wilberforce so that no stream of any size runs into it. A branch 

 glacier from that of the Upper Rakaia passed by the valley of the 

 Cameron River to Lake Heron and Lake Acland, and emptied into 

 the valley of the Rangitata between Mount Harper and the Moor- 

 house Range. § Sugar Loaf, near Lake Heron, shows admirably 

 the height to which the ice of this glacier reached. After it had 

 melted away a large lake was left, of which Lake Heron is but a 

 remnant The Rakaia glacier at the time of its greatest extension 

 appears to have been between fifty and fifty-five miles in length. 



* Hutton, Kepoits Geol. Explorations. 1,h73-4, p. 52 ; Travers, Quar. Jour. Geol. Soc. vol. 

 22, p. 254, and Trans., N.Z. In-t., vol. 6, p. 297; McKay, Rep. Geol. E.xplorations, 1878-9, 

 p. 121 ; Cox, Hep. Geol. Explorations, 1SK4-5, p. 9. 



t Haast, Report on Geologv of Canterburv and Westland, pp. 212 and 391 ; Report Geol. 

 Exploration, 1871-2, p. 31-3o;' Hutton, Trans , X Z. Inst., vol. 16, p. 449, and vol. 19, p. 395. 



t Haast, Report on the flead-Tvaters of the R. Rakaia, Christchurch, 186fi ; Rep., Geol. 

 Exploration, 1871-2, p. 32, Ge^'l. Canterburv and Westland, p. 386; Hutton, Rep., Geol. 

 Explorations, 1873-4, p. 52; Cox, Rep., Geol". Explorations, 18S3-4. p. 43 



5 Haast, Rep. Geol. Explorations, 1873-4. map opposite p. H) ; Geol. Canterbury and 

 Westland, Christchurch, 1879, p. 387 ; Cox. Rep. Geol. E.^plorations, 18S3-4, p. 43. 



