340 The Philippine Journal of Science 



Wood fine to medium textured, fairly straight grained, mod- 

 erately hard to hard, moderately heavy to heavy; specific gravity, 

 0.793. 



Microscopic features. — Vessels numerous, small, 44 to 170 fi 

 (average, 147) in diameter, rounded to oblong in transverse 

 section, solitary or in occasional groups of 2; tyloses sparse. 

 Tracheids and fiber tracheids wanting. Libriform fibers nu- 

 merous, small (17 by 1,370 /a), with walls 4.4 fi in thickness, in 

 indistinct radial rows. Vertical parenchyma vasicentric but 

 tending toward diffuse-zonate ; diffuse parenchyma sparse, in- 

 conspicuous. Resin cysts in interrupted, concentric lines, 

 inconspicuous. Horizontal and vertical idioblasts present, the 

 latter predominating. Wood rays small (4 by 80 cells). Or- 

 ganic infiltration scanty. 



Remarks. — Used for the same purposes as Hopea acuminata, 

 which it resembles in gross characters, but separated micro- 

 scopically according to the features enumerated in the key. 



Hopea pierrei occurs throughout the Islands from northern 

 Luzon to northern Mindanao, but is best known in Laguna and 

 Tayabas Provinces, Luzon. 



