IX, A, 5 Brown and Mathews: Dipterocarp Forests 421 



outside of the region in which they occur is naturally due to 

 the fact that only the better grades have been exported, and 

 these the world markets have accepted as finishing lumber. 

 Furthermore, the primitive methods of lumbering, which until 

 recent date have been the only ones in use in the tropics, have 

 made lumbering expensive and the handling of large trees 

 impossible. Under these conditions, the only woods which could 

 be exported with profit have been the very hard ones which 

 are in constant demand for ornamental purposes and for which 

 very high prices are paid. With the introduction of modern 

 logging machinery, lumbering in the Philippines is becoming 

 constantly- cheaper, the supply of construction timber is exceed- 

 ing the local demand, and exportation of various classes of 

 lumber has begun. 



Comparatively little is known of the class of timber existing 

 in the extensive forests of tropical Africa and South America, 

 but judging from descriptions of forests in both of these regions 

 the stands are dense and are composed of large trees. Pechuel- 

 Losche ^^ in his description of the west African rain forest says : 



There is rather a rich repetition of certain forms developed into giants 

 which invest it with an imposing uniformity. 



Again, Stanley ^* describes the forests of the great Congo 

 region as composed largely of great buttressed trees with clean 

 boles. Schimper ^^ in speaking of the forests of tropical Amer- 

 ica says: 



The tropical virgin forest of America has very properly acquired the 

 highest reputation. The ordinary descriptions of tropical virgin forests 

 chiefly refer to it * * *. I found it, in many ways, far more majestic 

 than in Java, owing to the larger dimensions of the trees, * * *. 



It seems not unlikely that further exploration of these regions 

 will develop the fact that they are capable of supplying a large 

 proportion of the construction timber of the world. 



COMPOSITION AND ARRANGEMENT OF PHILIPPINE DIPTEROCARP FORESTS 



Most of the descriptions of tropical forests have been written 

 by naturalists who were looking for new and curious forms of 

 plants. Their descriptions and pictures have, therefore, led to 

 the popular impression that tropical forests are composed largely 



" Pechuel-Losche, E., Die Loang-Expedition. Abth. Ill, Halfte 1. Leip- 

 zig (1812). See Schimper, Plant geography. Oxford (1903). 



" Stanley, H. M., In darkest Africa. C. Scribner's Sons, New York 

 (1913). 



" Schimper, A. F. W., Plant geography. Univ. Cambridge Press, Oxford 

 (1903). 



