Hzcron.— Geographical Botany of New Zealand. 159 
limit of the forests. The most striking feature of this western bush is, 
however, the wonderful luxuriance of cryptogamic plants, every shrub and 
tree being loaded with damp lichens, mosses, and fungi, which rapidly 
destroy the timber. 
A2.—The mixed bush of the East Coast presents a marked difference 
from that on the west: on the whole, the timber is better grown and of 
larger size, and there is a much greater variety of Pines. Its most charac- 
teristic development is around Dunedin, where it is rare to meet any Iron- 
wood, Karmahi, or Birch, which are so common on the west, Black and 
White Birch being wholly wanting. 
Zone B.—In crossing the alpine ranges to the eastern side, the upper limit 
of the forest is at a less elevation, reaching to only 3,500 feet, and along 
the eastern slope of the mountains consists nearly wholly of Birch trees, 
with patches of mixed bush in favourable situations by the sides of the 
larger lakes. The valleys in this district are generally oceupied by a dense 
scrub, consisting of Veronicas, Cassinias, and Olearias, resembling somewhat 
the sub-alpine flora, while the woods are skirted by a luxuriant growth of 
the handsome Lace-bark tree (Plagianthus lyallii), with its delicate green 
leaves and large white flowers. 
Zone C1.—4As has been already observed, the influence of the mountains 
in intercepting moist westerly winds, has given to the district in the 
central part of the island a flora which possesses almost a continental or 
arid type. 
Cryptogamie plants, which are generally so abundant in New Zealand, 
are almost wanting, being largely reduced in relative percentage to the 
phanerogamie flora. 
The plains are covered with grasses, the roots of which are gathered into 
tufts or tussocks, intermixed with the Bayonet grass or * Wild Spaniard " 
(Aciphylla colensoi), Toumatakuru (Discaria toumatou), and a great variety 
of the New Zealand brooms (Carmichelia); with small Orchids, Pimelias, 
and ericaceous plants. 
Advancing towards the east, the grasses acquire a different character, in- 
dicating the influence of moisture derived from the eastern sea-board. 
The yellow tussock predominates, and is intermixed with a rank growth 
of fern (Pteris aquilina, var. esculenta), Tutu (Coriaria), several species, 
Flax (Phormium tenax), and the soft-leaved Spear-grass (Aciphylla squar- 
rosa), all of which latter plants rarely occur in the interior or lake 
distriet. 
Zone D1.—This is the zone of sub-alpine plants, which is especially 
distinguished by the prevalence of large bunches of Snow-grass, which term 
includes various species of Danthonia and Agrostis, intermixed with scrubby 
