thxON — Mahogany, Recognition of some Different Kinds. 475 



laminae ; 5-21 between rays.— Circumvasal parenchyma narrow, often with 

 dark contents ; laminae 1-3 cells thick, inconspicuous. Eays conspicuous, 

 dark. 



T.S. — Eays irregular in size and arrangement, about 25 in 2-rnm. field 

 total width in 2 mm. = 041mm Height = 0-10-0-80-1-54 mm., 2-50 cells 

 width = 0-02-0-05 mm. ; 1-, 2-, 3-ply. Margin distinct, cells high, triangular, 

 often several cells deep. Frequent deposit in all ray-cells. — Fibres septate. 



R.S. — Marginal cells square or vertical rectangles. 



Note. — Foxworthy (7) says Serayah is derived from Uopea or Shorea spp. 



40. Shorea robusta. 

 No. 191, in School of Botany, Trinity College, Dublin, without record of 

 origin, labelled " Shorea robusta, Sal." PI. XLIL, figs. 121, 122, 123. 



Pale brown, dull and roey ; vessels scattered, close, with mealy margin in 

 C.S. In T. and E. sections, with glistening light contents (tyloses). 

 Occasional narrow zones of dense fibres, almost free from vessels. Parenchy- 

 matous laminae very close, thin, and often narrow in tangential direction ; 

 irregular, about 0-2 mm. apart. Sp. gr., 0-87. 



C.S. — Vessels circular, scattered, seldom in contact with one another. 

 M.T.D. = 0-20 mm., 24 in 2-mm. field. With tyloses.— Fibres very thick- 

 walled. Lumen obliterated. — Circumvasal parenchyma 2-3 cells thick, 

 spreading tangentially into laminae, 1-10 cells thick; empty.— Eays filled. 



T.S. — Vessels packed with tyloses. Eays irregular in size, acute, sides 

 irregular and sinuous, about 30 in 2-mm. field. Total width in 2 mm. 

 = 0-43 mm. Height = 093 mm. (045-2-00 mm.). Width = 0-056 mm. 

 1 , (2-) 3-, 4-ply. Margin indistinct. Inner cells thick-walled, filled. 



R.S. — Fibres non-septate. Occasional vertical rows of crystals. 



Note. — Foxworthy (6) states rays are mostly 4 cells wide. 



41. Eng.Teak. 

 No. 117, from commercial source, labelled " Eng Teak." PI. XLIL, 

 figs. 124, 125, 126. 



Brown, with narrow (1 mm. thick) layers of dense and dark-brown 

 tissues. Vessels usually filled with buff, mealy substance (tyloses) or black 

 deposit, or more seldom with white substance, avoiding dense layers. Sticky 

 resinous substance exudes from vessels in hot weather. No parenchymatous 

 laminae visible. Sp. gr. = 0'87. 



