River-bed. — Grassland. 167 
5. North Island river-bed. 
My notes on the North Island formation are altogether insufficient. River- 
bed from the Dividing Range may contain Raoulia tenwicaulis, species of 
Epilobium and perhaps thickets of Cassinia lepiophylla. In the Egmont- 
Wanganui district Veronica catarractae var. lanceolata and Gnaphalium keriense 
are characteristic and there may be young shrubs, especially Carmichaelia 
australis, Coprosma robusta and Veronica salicıfolia. 
7. Grassland. 
a. General. 
The natural grasslands of New Zealand, here termed steppe, differ es- 
sentially from meadows of the Old World. Green, flat-leaved, turf-forming 
grasses do not rule, in their stead is brown tussock composed of closely- 
bunched filiform rolled leaves and slender culms. 
Grassland is far more abundant in the South than in the North Island, 
its presence depending on a drier climate than rain-forest can endure. There 
is nevertheless evidence that some of the apparently primeval steppe may have 
been produced through forest fires, a supposition partly based on Maori 
tradition and partly on the presence of the remains of burnt trees in Central 
 Otago, Canterbury and elsewhere. 
| Tussock-steppe is no longer virgin. Continual grazing, periodical burning 
‚and the presence of numerous well-established introduced plants has brought 
about no few changes, but these are not sufficient to have obliterated the 
primitive stamp in many localities, or to have eradicated any species. 
The association is wanting in the Northern botanical province; its place. 
being taken by heath. Further S., it occurs in various localities E. of the 
. central mountain-chain and on the higher 'parts of the Volcanic Plateau. In 
the South Island, it occupies wide areas on the E. of the Divide being the 
formation of greatest physiognomic importance. Also, there are considerable 2 
.  stretches in the Ru use al district. MbRte eh the. formation intergrac | 
with moor...:. et 
+ 0 I some localities, oitass ost which = Be er vis Den 
| a by steppe; in other localities much Eraslahi has, DER, ing ie 
