INDO-MALAYAN WOODS. 507 



made up in a decidedly ornamental fashion; but it is as general con- 

 struction timber, where large quantities of good woods are required, 

 that the dipteroearps are most useful. There are a number of very 

 durable woods in the family and quite a number of fair durability, 

 which are very easily worked. 



The family is restricted to the Orient, being found in tropical Asia 

 from the Seychelles to New Guinea. 



The wood of the family is characterized by the presence of resin-ducts. 

 These are usually arranged in incomplete concentric lines, and some- 

 times appear at first sight to represent seasonal rings. However, this 

 irregular occurrence and the incompleteness of the rings is sufficient to 

 show very conclusively that they do not represent such periods of growth. 

 Seasonal rings are never present, so far as known. There is a wide 

 range of color and hardness. Pith-rays fine to moderately broad. Pores 

 small to large. Wood parenchyma irregularly arranged, usually scat- 

 tered, sometimes in discontinuous tangential lines. Two kinds of pith- 

 rays are sometimes present, as in Vatica and some species of Diptero- 

 carpus. 



The number of species in the family is large and many of them are 

 but incompletely known. When Brandis wrote his Enumeration (1895) 

 there were 385 species known. Since Unit time, there have been 25 or 

 :?(> species described and there are probably quite a number of undescribed 

 species in Sumatra, Borneo and other portions of Malaya. 



It seems that nearly all species in the family produce wood which 

 is utilized, most of it commercially; consequently the classification of 

 dipterocarp woods is an undertaking of some magnitude. There are 

 groups of species which correspond in structure and which are marketed 

 under the same name. An effort has been made to group the diptero- 

 carps according to the structural groups and to apply the most used 

 trade names to these groups. 



The following seem fairly distinct: vassal,-, chengal, yacal, peniow, 

 mangachapuy, mangasinoro, hipor. sal or guijo, apitong, tanguile, red 

 la linn, aha on, white latum, may apis. 



RASSAK. Plato XXYI1, fig. 85. 



This is variously known as rassdk, resale, resah balu, empadu, and 

 narig, and comes principally from species of Vatica and Cotylelobium. 

 It is found in Borneo, Sumatra, the Philippines, Ceylon and southern 

 India. Trees of this group are very widely distributed. Singapore 

 seems to be the principal market for tin 1 wood. It is probable that some 

 of the wood in the Singapore market under this name is supplied by 

 species of Slioira. The supply of rassdk in Borneo seems to be rather 

 limited. It is increasingly difficult to find huge trees. The tree seems 

 less gregarious than is the habit of many other members of the family. 



