Dixon — Mahogany, Recognition of some Different Kinds. 477 



E.S. — Eay marginal cells square or oblong, vertical. — Frequent parenchy- 

 matous laminae, 1 cell thick.— Fibres non-septate. 



Note. — This wood agrees closely in structure with that of the Diptero- 

 carpeae. and is possibly the wood of Bryobalanops aromatica Gaertn. f. 



43. Yang. 



No. 218, from commercial source, labelled." Yang, or bastard teak from 

 Moulmein." PI. XLIIf., figs. 130, 131, 132. 



Warm brown, with indistinct dark zones in which the vessels are scarcer; 

 distinctly roey and lustrous. Vessels with mealy margin. Parenchymatous 

 laminae fine, discontinuous, light ; 0-5-20 mm. apart. Sp. gr. = 070. 



C.S. — Vessels somewhat compressed tangentially, isolated or in groups of 

 two. M. T. D. = 0-26 mm. ; about 14 in 2-mm. field ; occasional tyloses. — 

 Fibres thick- walled, lumen often obliterated. — Circumvasal parenchyma often 

 conspicuous ; small amount of scattered parenchyma. Laminar parenchyma 

 3-10 cells thick, forming short plates in a tangential direction, chiefly in 

 connexion with the small vessels. — Pays conspicuous, with dark contents. 



T.S. — Rays irregular in size and arrangement, roughly of two grades, wide 

 and narrow ; 25-30 in 2-mm. field. Total width in 2-mm. field = 0-43 mm. 

 Height = 0-90 mm. (0-20-1 -50 mm.); 10-60 cells. Width = 0-01-0-07-010mm. 

 1-, 2-, 3-, 4-, 5-, 6-, 7-, 8-, 9-ply. Margin distinct, often of many cells ; middle 

 cells with small lumen, often with contents. — Fibres non-septate, 1-10 

 between rays. 



U.S. — Marginal cells of rays square or triangular, with thick pitted walls. 



Note. — This wood is not the bastard teak of Boulger(2), which is derived 

 from Pterocarpus marsupium Roxb. The latter, according to Gamble (8), has 

 very fine rays : cf. figs. 82 and 112. 



The wood resembles that of Shorea, and may well be one of the Diptero- 

 carpeae. Its structure agrees with Gamble's description of D. tuberculatus, 

 except in the absence of resin. 



44 . Tarrietia ja vanica. 



No. 85, from commercial source, marked " Philippine mahogany, Lum- 

 bayao." PI. XLIV., figs. 133, 134, 135. 



Dark rose-brown and lustrous, not roey. Fibres distinctly zoned, vessels 

 avoiding dense zones. Vessels large and very evident on radial and tangential 

 faces. Contents black or occasionally white. No parenchymatous laminae. 



