50 PHILIPPINE RESINS, GUMS, AND OILS 
The Bureau of Forestry has authentic specimens of resin 
from Hopea acuminata, Parashorea malaanonan, Pentacme con- 
torta, Shorea balangeran, Shorea eximia, Shorea negrosensis, 
Shorea palosapis, Shorea polysperma and Vatica mangachapoi, 
while Heyne reports that Isoptera borneensis yields resin in 
small quantities. 
Balau hardens only after long exposure, but most of the dip- 
terocarp resins harden rapidly to a dry, brittle consistency 
They vary from a light yellow or grayish tinge to almost black. 
Very little is known of the chemical composition or possible 
industrial uses of the various quick-drying dipterocarp resins. 
Genus ANISOPTERA . 
ANISOPTERA THURIFERA Blanco. (Figs. 14, 15). PALOSAPIS. 
Local names: Apitong (Sibuyan Island, Capiz); apnit, diung (Abra); 
bagobalong (Samar); bétes or létis (Masbate); ddgang (Rizal, Bulacan, 
Albay, Camarines); ddgum (Laguna, Tayabas, Albay); diéyong (Ilocos 
Sur, Ilocos Norte) ; lawdn (Rizal); lawdn puti (Nueva Ecija) ; létis (Ticao 
Island, Iloilo) ; mala-dtis (Rizal) ; maydpis (Rizal, Bataan, Zambales, Nueva 
Ecija, Bulacan) ; palosdpis (Zambales, Pangasinan, Bataan, Nueva Ecija). 
PALOSAPIS RESIN 
A resinous oil, frequently known as oil of palosapis, is obtained 
from the trunk of this species. This resin is very similar to 
balau from Dipterocarpus grandiflorus, is obtained in the same 
manner, and is used for the same purposes. ‘ 
Clover * says that an examination of the resinous oil from 
Anisoptera thurifera (which he called mayapis) proved it to be 
similar to that from Dipterocarpus grandiflorus and D. vernict- 
fluus, but that it dried much more rapidly than either of the 
latter; that it was light colored, apparently homogenous in 
composition, and so viscous that it could scarcely be poured.* 
Heating to 100° caused it to harden, and exposure to the air 
produced the same effect, changing it to a pearly, white solid. 
He found that it contained 15 per cent of water and 25 per 
cent of sesquiterpene oil, which could be removed by careful 
distillation without decomposition. The residue was hard. 
The oil redistilled at 17 millimeters, possessed the characteristic odor 
of the resin, and was very light yellow in color. Boiling point, 132° to 
30° 
140° (17 millimeters. Specific gravity, ( 5° )=0.9056. 
Anisoptera thurifera reaches a height of 40 to 45 meters and 

* Clover, A. M. Philippine wood oils. Philippine Journal of Science, ¢ 
Volume 1 (1906), page 191. 
