446 Scientific Proceedings. Royal Dublin Society. 



29. 



32. 



Circumvasal parenchyma sometimes marked and spreading tan- 



gentially. 26. " African cedar." 



Circumvasal parenchyma thin and inconspicuous, not spreading 



tangen tially, 30 



Average height of rays about 05 mm. Maximum rising to 09 mm. 

 35-40 rays in 2 mm. field T.S. 4. Carapa gmanensis. 

 I Average height of rays about - 8 mm. Maximum rising to 1*5 mm. 

 about 25 rays in 2 mm. field T.S. 39. " Eed Serayah." 

 Circumvasal parenchyma forming a complete thin dark sheath 

 round the vessels. M.T.D. = 045 mm.-0'50 mm. 

 31. -I 44. Tarrietia javanica. 



Circumvasal parenchyma usually incomplete. M.T.D. less than 



0-30 mm., 32 



Rays occasionally 5-ply ; average height = 1*0 mm. ; 20 or less in 



2 mm. field T.S. 12. " Dalli." 



Rays never 5-ply ; average height, less than - 9 mm. : 25 or more 

 in 2 mm. field T.S. 5. Carapa sp. (Demerara). 



/ Parenchymatous laminae present, 34 



33. \ Parenchymatous laminae absent or rare. 



( .45. Acacia koa. 



Rays 100 or more in 2 mm. field T.S. 29. Trichilia emetiea, 

 Rays about 50 or 60 in 2 mm. field T.S. 36. Dysoxylon lessertianum. 



Some rays 4-ply, 36 



Rays rarely if ever 4-ply, 38 



Average heightof rays about0 - 30 mm. 38. "Thitka" Pentace bur- 



manica ? 



Average height of rays - 6 mm. or more 37 



Parenchymatous laminae rare or absent. Much scattered paren- 

 chyma. 27. " Cape Lopez." 

 Parenchymatous laminae close but interrupted. Scattered paren- 

 chyma insignificant. 14. " Cedrana." 



/ Parenchymatous laminae rare or absent. 39 



3S. Parenchymatous laminae close (0'2 mm. or less apart). 



' 7. Cariniana pyriformis. 



I Fibres thick-walled, lumen often obliterated. 

 39. ■ 11. " Turiballi." 



( Fibres thin-walled 40 



/ Circumvasal parenchyma inconspicuous. 



23. Aucoumea klaineana. 

 40 i 



Circumvasal parenchyma 4-10 cells thick. 



15, " Panama mahogany 



34 



' 



6 



I 



7.-! 



