342 The Philippine Journal of Science 



Fig. 3. A typical mature resin duct, showing a wide cavity lined * 



4. At 



ing the cl 



Plate 6 



Parashorea malaanonan, radial section of wood, 22677 B. F.; X 50. N01 



the heterogeneous cells composing the wood or pith rays. 



Plate 7 



Parashorea malaanonan, radial section of wood, 22677 B. F. ; X 200. Sho\ 



ing idioblasts with calcium oxalate crystals in them. 



Plate 8 



Parashorea malaanonan, tangential section, 22677 B. F.; X 50. 



Fig. 1. Longitudinal view of a bordered pit leading from one vessel 1 

 another vessel. 



2. Longitudinal view of a bordered pit leading from a vessel to 



tracheid. 



3. Lateral view of a bordered pit leading from vessel to vessel. 



4. Longitudinal view of a semibordered pit leading from a vessel \ 



a wood or vertical parenchyma. 



5. Longitudinal view of a semibordered pit leading from tracheid 1 



8. Longitudinal view of a semibordered pit leading from s 



9. Longitudinal view of a bordered pit leading from a libriform fiber 

 to another libriform fiber. 



10. Vertical view of a bordered pit. 



11. Vertical view of simple pits. 



12. Longitudinal view of simple pits leading from wood parenchyma 



to parenchyma cells. 



Plate 10 

 Vatica mangachapoi Blanco, cross section of wood, 90 AS B. F.; X 50. 



Plate 11 

 Dipterocarpus grandiflorus Blanco, cross section of wood, 17581 B. F.; X 50. 



Plate 12 

 Dipterocarpus vemicifluus Blanco, cross section of wood, 21S1 B. F.; X 50. 



Plate 13 

 Dipterocarpus lasiopodus Perkins, cross section of wood, 2031 Merrill; X 50. 



