714 
WHITFORD. 
The following shows its character : 
Table XII . — Stand of trees 30 centimeters and over in diameter on the lower 
slope type of the Aroroy region, Masbate ( average of 16 acres). 
Scientific name. 
Common name. 
Average 
number 
of trees 
per 
hectare. 
Per 
cent. 
Dipterocarpaceae: 
Parashorea plicata Brandis — 
Bagtican lauan___ 
47. 5 
56. 88 
Guijo _ 
. 7 
.82 
Combretaceae: 
Terminalia quadrialata Merr. - . 
Toog _ _ 
12 
14.36 
Sterculiaceae: 
Magalipac 
4.2 
5.02 
Anacardiaceae: 
Dao 
1.7 
2.02 
Amuguis _ 
. 5 
.6 
Legiminosae: 
Narra_ . _ _ 
1.5 
1.8 
Olacaceae: 
Strombosia philippinensis Rolfe — - - 
Tamayuan 
.9 
1.1 
All others _ _ 
14.5 
17.4 
Total 
83. 5 
100 
It is thus to be noted that 47 trees out of 83, or approximately 57 per 
cent of the stand, belong to two species of the dipterocarps. A discussion 
of the other types of forest in this region is reserved for another paper. 
FORESTS OF THE ZAMBOANGA PENINSULA IN MINDANAO. 
In cooperation with W. I. Hutchinson, the forests of a lumber con- 
cession located at Port Banga at the head of Zamboanga Peninsula on 
the Island of Mindanao were investigated. The work here was similar 
to that accomplished in Mindoro and Negros. This tract, comprising 
355 square kilometers, has about 52 per cent (or 186 square kilometers) in 
virgin forest. Of this, 16,144 hectares or 86.37 per cent is forest in which 
the dipterocarps predominate. 
The topography of the region is rough and broken. It is composed 
mostly of low irregular ridges 15 to 100 meters in height extending into 
headlands bordering on the sea. These lead inward to the base of the 
mountains. The rivers are small and beyond tidal limits are hill streams 
with cahon-like valleys whose beds are full of bowlders and rock outcrops. 
Tables XIII and XIV show the stand and volume on two types. 
