100 Transactions. — Botany. 



stable for the most part, and bear in consequence a mora 

 abundant vegetation than the first named. 



Passing in a westerly direction from the dunes, the Can- 

 terbury Plain is entered upon, through which the river flows 

 in a fairly straight course over a wide stony bed, margined 

 occasionally with wet ground, in which situations Arundo 

 conspicua, Phormium tenax, and often Cordyline aiistralis are 

 plentiful, and become a pleasing feature in the landscape. 

 On the shingly river-bed, in its firmer portions, various species 

 of Baoulia flourish, forming large silvery, moss-like patches. 

 On either side of the river are stretches of often extremely 

 stony ground, looking in some places almost as if it had been 

 paved, and having for a plant-covering a low-growing and 

 very characteristic vegetation, amongst which the dwarf, 

 leafless, shrubby Carmichaelia nana is conspicuous. Inter- 

 spersed with, and of much greater extent than, this stony 

 ground are larger or smaller tracts of land suitable for culti- 

 vation, and varying from very light sandy and stony soil to 

 rich dark-coloured loam of very great depth, the whole form- 

 ing, indeed, one of the finest farming districts in New Zealand. 

 The richest part of this land was for the most part origin- 

 ally swamp, occupied by Phormmm, but such is now almost 

 altogether reclaimed, and yields immense crops of cereals, 

 potatoes, and the like, especially if the season be not too wet. 

 These swamps and their immediate vicinity were most likely 

 at an earlier date occupied by forests. This subject will 

 receive further consideration when the pine forest plant- 

 formation is treated of ; here it need only be mentioned that 

 a small portion of the primeval forest still remains in very 

 fair preservation, having been well cared for by its owner, Mr. 

 John Deans, of Riccarton, and affording a most valuable record 

 of the former arboreal vegetation. 



At about fifteen miles from the sea, in the neighbourhood 

 of Courtney, some interesting low sandhills, mounds, or ridges 

 are met with, having Isolejns nodosa on the sunny and 

 Phormium tenax on the south-west side, with Sopliora prostrata 

 near their bases. 



From the sea to the mountains the plains rise gradually at 

 an average of 10-9 m. per mile, until at near the base of 

 the latter — Mount Torlesse — they reach a height of 450 m. 

 (For full particulars as to the fall of the Canterbury Plains, 

 see Haast, loc. cit., p. 403.) 



At a distance of at from six to seven miles from where the 

 river leaves the plain occurs the lower gorge ; here the river 

 has cut for itself a passage right thi'ough an isolated hill — 

 Gorge Hill — standing towards the middle of that part of 

 the plain, a most remarkable phenomenon when we consider 

 that the river appears to have had the whole of the plain 

 at its disposal for a bed. An account and probable explana- 



