CussEN. — 0)1 tJie Waikato Biver Basins. 411 



of the most recent occurrence, is that shown on Mr. E. B. 

 Walker's property at Mona Vale, four miles south-west from 

 Cambridge (PL XXXV.). A drain was cut about a mile in 

 length through a neck of dry land, to drain the Mona Vale 

 Swamp into a dry gully which led to the Waikato Eiver. 

 During a heavy flood some years ago a scour was started in 

 this drain, which soon formed a gully from 60ft. to 70ft. in 

 depth and in some places several chains across. At the 

 bottom of this gully the ancient laud-surface was exposed to 

 view. It consists of a stiff, brown, marly-looking soil, ap- 

 parently of excellent quality. The trunks of many trees are 

 lying on the old land-surface, and some were found to be 

 standing, with their roots penetrating the old soil, as they 

 grew. The present land- surface is perfectly level, whilst the 

 ancient sm-face is found at various depths from 30ft. to 60ft., 

 showing the old contour of the land. The timber found here 

 seemed in tolerably good preservation. This is suggestive of 

 a very interesting thought : that, if the country was inhabited 

 previous to this submergence, some relics of the animals or 

 men who lived in it might come to light some day on the old 

 land-surface. 



Characteristic of the middle Waikato basin are the numerous 

 funnel-shaped holes to be seen everywhere throughout the 

 alluvial deposits. They were formed by the subterranean or 

 soil waters in passing along beneath the surface of the earth. 

 They create small caverns, and, finally, underground streams, 

 which draw away the loose material from the surface, and 

 frequently form symmetrical funnel-shaped holes — the " pot- 

 holes " of the settlers. Probably the water, being charged 

 with carbonic acid, was thus enabled to dissolve some of the 

 river-gravel through which it passes, and by degrees to become 

 a small running stream. 



Now, it seems very evident that these deposits in the 

 middle Waikato basin could never have been laid in the 

 bed of a lake nor by the waters of the Waikato at all 

 with the levels of the land as we now find them. The lake 

 would have four outlets — one at Morrinsville, one at Hapu- 

 kohe, one at Matahura, and one at Taupiri, all 100ft. below 

 the level of the bed of the lake in the centre ; therefore 

 the waters would not be impounded to place the deposits. 

 Neither is the action of the sea admissible : the character 

 of the deposits, the mode of their distribution, and the levels 

 of the valley as they now stand, preclude this, the western side 

 of the basin being lower than the eastern side, where the 

 estuary would have its outlet. To local movement, or oscilla- 

 tion in the level of the land within the basin, it would seem 

 we must attribute the phenomena. The Waikato, on debouch- 

 ing through the Maungatautari Gorge, would probably occupy 



