162 b The Plant Formations, 
Near Lake Manapouri to the E. there is an extensive shrub-moor. There 
is a great depth of peat. Dracophyllum Urvilleanum (one of its varieties) forms 
so close a mass that nothing else can be seen at even a short distance away. 
Within the scrub there is Sphagnum, Hypolaena, Cladium teretifolium, Oreobolus 
sirictus and other bog species. 
A rather remarkable association occurs on those flat, badly drained areas 
of the North-western and Western districets known by the Maori name of 
“Pakihi”. All that I have studied have been burned repeatediy, and although 
the vegetation bears a primitive stamp through the absence usually of introduced : 
plants, one can but guess at the composition and arrangement of the Pe = 
vegetation. 2 
The soil-conditions are different from those of true moor. a, is. 
frequently ancient coastal terrace, and the subsoil consists altogether of stones 
which through the presence of “iron pan” are impervious to water. The upper 
soil consists of clay capped by a layer of peat, usually quite thin, though 
this may be wanting. Normally, the ground is extremely wet. Where Zepto- 
spermum does not dominate the covering is a combination of Cladium tereti- 
folum, C, glomeratum, C. capillaceum (at times), C. Vauthiera, Hypolaena 
laterifiora and Gleichenia dicarpa, just as ordinary peat-moor, in fact. Zyco- 
podium ramulosum is abundant, and there may be Gahnia-tussocks. 
On the pakihis of the North-western district the northern Zpacris yaucifore: 
is abundant. Zzparophyllum Gunniü, also common on Stewart Island. moor, 
and Gentiana Townsoni are plentiful. The very local Siphonidium longiflorum 
absent over wide areas, nor does it seem to be making peat. ee 
‚at all stages of development is everywhere. 
Doubtless the open spaces were once in large part forest, but the native. 
name proves that there was here a primitive moor-association. And yet it is 
one in which peat was virtually absent!  . 
B River-bed. BEE er 
| ” a. General. . | 5 
| River-bed i is ER of those ee plains formed by the various 
‚streams which still bear be stony burden from the lofty ranges, These be 
extend from the  sea-coast ar into the # Their ‚greatest development 
is to the E. of the Divide in the South Island, though on the W., althougl 
shorter, they are still ve considerable. In the North Island, ziver-bed is ‚much 
less in evidence. er 
Between the venkticin of ehe at. Are altitudinal belts it is not 
easy to draw the line; ecological differences are slight, and many species occur 
throughout. Rainfall is the chief factor. that governs the combinations; thu 
in the South Island the humid W. favours the DseBeE of plants in the lov 
| lands which. are ag en in the dryer E. = 
