44 
The prominence of orchids, Myrtaceswe, Rhododendrons, Styphelias, and 
Vacciniums, in relation to other plants, is equally emphasized, but members 
of the Araliacese, an old type of plant so prominent in the Arfak of New 
Guinea, are, so far as we know, absent on the N. Bornean mountain. 
From descriptions of the Philippine mountain-ridge vegetation it would 
appear that the Papuan facies again predominates, thus approximating it to 
that of the Arfak and Mt. Kinabalu, the absence of araliaceous types being 
less marked, though of the typical Papuan genera Anomopanaz is represented 
by one species, and Kissodendron and Mackinlaya are absent. Phyllocladus 
hypophyllus is common to all, with allied Dacrydium and Podocarpus spp. 
Glochidion Merrillii is also common to the Arfak, but a thinning out in the 
number of Styphelia and Vaccinium spp.is apparent, while the Rhododendrons 
show a great reduction in variety of type. 
4, THE MOUNTAIN FOREST FLORA OF THE ARFAK MOUNTAINS 
POSSIBLY REPRESENTS OLDEST PAPUAN TYPE, 
It is in the Arfak alone, of all the Papuan mountain ranges of similar or 
greater altitude, that two different localities have been worked over on three 
separate occasions. This fact gives a wider field of comparison in relation 
to this range. On comparing the general type of vegetation and the 
generic and specific distinctness of the plants so far collected on this range 
with those ‘known from similar localities, one feels inclined to look upon 
these granite mountains as carrying an older part of the Papuan flora. 
Where so little is known, however, of the mountain flora of the country as 
a whole, and collections remain limited to vertical sequence, it is impossible 
to base such an impression on any actual fact, and the hypothesis is only 
worth advancing as a possible consideration for future workers. 
The contrast is very striking between the recent “korang” belt, from 
which this range on the east rises almost without transition as abruptly as 
the mountains on the north from the sea, and the well-defined limits and 
deep soil of the foot-hills and lower ranges. The extreme homogeneity of 
the mountain forest zone, the extraordinarily small incidence of outside or 
immigration plants, combined with the relatively broad crests of the ridges 
and the tremendously weathered condition of the main range, are all facts 
which point to general stability in condition, spreading over a considerable 
epoch of time. 
The climate of the Arfak would also seem to be more favourable than on 
other ranges, and the nature and structure of the plants are not so limited 
by the edaphic and atmospheric factors which play such a large part in the 
restriction of floral conditions on Kinabalu. 
For instance, all the Arfak plants show coriaceous to very small leaves, 
and the hairy covering or tomentum, common to many of the Kinabalu 
