48 MISS L. S. GIBBS ON THE FLORA AND PLANT FORMATIONS 
the Penibukan ridge and from places on the south-western spur; above 
Kamburangau the trees may be of an appreciable size, as on the Maraiparai, 
and where the mossy forest succeeds the high forest above the Lobang ledges. 
This type of forest also seems to be limited to very sheltered positions, where 
the tops of the trees form a dense covering and the circulation of the air and | 
the consequent evaporation is practically nil. 
f. Plant Formations and Associations of Kinabalu. 
Dr. Stapf, following Junghuhn, has divided this mountain into zones 
of vegetation; but the Javanese conditions are so dissimilar to those 
obtaining in N. Borneo that I hardly think any comparison on an ecological 
basis will hold good, though from a systematie point of view the secondary 
and primary forests i in the two regions are practically composed of identical 
species or showing very close affinity, 
Java has been under scientific European control for over a century. It 
has ranges of mountains running up to 5000-6000'; culminating in more or 
less rounded peaks of greater altitude, and recent isolated volcanoes. As in 
India, expert forest control is very strict and all the ridges are left in virgin 
forest above 4000'. Below this altitude the whole land is under cultivation, 
controlled in the best interests of the land and of the people by expert agri- 
culturists. Under these conditions one can well understand that a division 
of the country into plant-zones is a correct expression of the features of the 
plant-covering of the island. This remark would also apply to the mountain 
peaks, as on these, owing to their isolated and more or less symmetrical form, 
all sides would be exposed to equal insolation, precipitation, evaporation, 
and wind-incidence, combined with the certain factor of a daily periodicity 
of rain. 
In N. Borneo none of these conditions obtain. The daily periodicity of 
rain is not the constant factor that it is in W. Java. During my stay at 
Tenom there was very little rain at all, and that which did fall was not to be 
reckoned on, at any definite time of day. On five days spent on Kinabalu 
itself rain only fell on one afternoon and night, and the mountain was clear 
for days after, in fact till I left the country in the beginning of March. 
The primary forest is also anything but a constant feature so far as altitude 
is concerned, and also very limited in its general incidence. The whole 
country is covered up to 2000—4000' with secondary forest, subject to the 
influence of a more or less defined sequence of cultivation through a series 
of years, according to the needs of a fluctuating and sometimes very small 
population, as, for “example, in the Murut country. This secondary forest 
comprises Stapf’s “ hill zone” from sea-level up to 3000’, but it may run 
up to a much higher altitude. 
