478 Scientific Proceedings. Royal Dublin Society. 



Rays dark-red brown, very marked on radial face, contrasting strongly with 

 silky fibres, tall Sp. gr. = 0-65. 



C.S. — Vessels circular, scattered. M.T.D. = 0-45 mm. ; 5-10 in 2-nun. 

 field, often with dark contents. — Fibres in dense zones thick-walled. — 

 Gircumvasal parenchyma forming a dark margin 1-3 cells thick round vessels. 

 Contents dark. — Rays filled with dark contents. 



T.S. — Rays irregular, sides parallel, acute, 20-30 in 2-mm. field. Total 

 width of rays in 2 mm. = 0*46 mm. Height = P56 mm. Width = 0T0 mm. 

 1-, 2-, 3-, 4-ply. Margin not always distinct. Often covering over the sides 

 of the rays is a layer of rectangular erect cells, sometimes with dark contents. 

 Middle cells small, rounded, thick-walled, with contents. 



U.S.— Fibres with occasional septa, regular. — Rays dark, with vesicular 

 contents. 



Note. — Mell (10) states that Lumbayao mahogany is the wood of Tarrietia 

 sylvcttica Merr. or of T. javanica Bl. 



Foxworthy (6) states that Lumbayao is botanically unknown. His micro- 

 photo as far as can be made out agrees with the above sample, but he describes 

 the wood as ring-porous, and his sample had a sp. gr. of 0-55 ; but in a more 

 recent paper (7) lie refers Lumbayao to Tarrietia javanica Bl., illustrating 

 it with the same microphoto. 



45. Acacia koa. 

 No. 212, from commercial source, labelled "Koa grown in Philippine Is." 

 PL XLIV., figs. 136, 137, 138. 



Golden-brown, lustrous and roey, hard, polishes on end grain ; tends to 

 split radially and tangentially. Ill-defined zones of light and dark. Vessels 

 scattered, not zoned. No parenchymatous laminae visible. Rays very fine. 

 Sp. gr. = 0-76. 



C.S. — Vessels tangentially compressed, scattered, isolated, or in radial 

 groups of 2-4 ; often with black contents. M.T.D. = 0-14 mm. ; 8-10 groups 

 in 2-mm. field.— Fibres thick-walled; 2-35 between rays.— Parenchyma 

 circumvasal irregular, 0-5 cells thick. — Rays narrow, filled. 



T.S. — Rays irregular, not uniform ; about 100 in 2-mm. field. Total width 

 in 2 mm. = 0-26 mm. Height = 1-25 cells, 0-01-0-40 mm. Width = 0-01- 

 0-03 mm. 1-, (2)-ply. Margin not differentiated, all cells, with contents. 



R.S. — Wood parenchyma only circumvasal. — Fibres non-septate.— Rays 

 of prostrate cells only. 



Foxworthy (7) refers Koa wood to Acacia koa Gray. 



