THE STRUGGLE FOR EXISTENCE 209 
appreciably felt. As we ascend the mountain sides 
the slopes become more exposed to wind and the 
extremes of temperature are greater, so that the mixed 
forest of necessity gives place to the hardy beech, 
which now becomes the dominant tree. Ascending 
still further we reach the sub-alpine scrub, beyond 
which is the alpine meadow, succeeded finally by the 
desert region at the summit. 
LD. Cockayne, Ph.D., F.R.S., photo 
Interior of southern-beech forest of wet district, Arthur's Pass, at about 
2,800 feet altitude. 
A walk from Ohakune to the summit of Ruapehu 
will show all these grades of vegetation. At Ohakune, 
at an elevation of about 2000 ft., the forest is mixed in 
character, tall and luxuriant, and, as in most other 
lowland districts throughout New Zealand, typical 
rain-forest. The rimu and matai are the dominant 
trees, but the tawa, mahoe, wineberry, panax, horopito, 
and fuchsia are also present. The ascent from Ohakune 
is at first very gradual, and just as gradual is the 
O 
