CLASSIFICATION OF HARD-WOODS 49 



ttt Some of the pith-rays very broad and easily visible 

 to the naked eye. Oaks, Quercus. 

 X Pores in summer wood very fine, numerous and 

 crowded : heartwood light brown. White Oaks, 

 Q. alba, hicolor, paMstris, obtusiloba, etc., in U.S.A. 

 and Robur in Europe. 

 %% Pores in summer wood fewer but larger : heart- 

 wood dark brown. Red and Black Oaks of 

 U.S.A., Q, rubra, tinctoria. 

 ttt Pores few, graduaUy but sHghtly diminishing 

 across the entire ring : wood very dense and 

 heavy. Live Oaks, Q. virens of U.S.A., Ilex and 

 Suber of Europe. 

 ftft Pith-rays moderately broad and distinct : vessels 

 in spring wood very large, those in summer wood 

 much smaller, 1-8 together : heartwood brownish 

 yellow : sapwood white. Judas-tree, Cercis. 

 **** Vessels in summer wood mostly but little smaller 

 than those of the spring wood, scattered, solitary^ 

 or few together. Mostly hard, heavy woods. 

 f Erne peripheral lines of wood-parenchyma : pith- 

 rays fine : zone of vessels interrupted : summer 

 wood reddish nut-brown. Hickories, Hicoria. 

 ft Similar, but with blackish heartwood. Persimmon, 



Diospyros virginidna, 

 ttt Vessels distinct and large, sometimes filled with 

 white phosphate of lime : pith-rays fine, distinct, 

 light-coloured: wood brownish-red. Ted^\,TeGt6na. 

 tttt Vessels equally distributed : pith-rays fine, dis- 

 tinct : wood a warm red brown, often beautifully 

 figured. Mahogany, SwieUnia MaMgoni. 

 ttttt Vessels very large, open or partly filled with a 

 brown resin : pith-rays distinct : heart- wood cin- 

 namon brown, very soft, fragrant. Honduras 

 Cedar, Oedrela odordta. 

 6. Vessels in the spring wood not larger, but generally more 

 numerous and crowded than in the autumn wood, 

 (i) Pith-rays distinct. 

 * Heartwood reddish-brown, zone of vessels in spring 

 wood lighter coloured : vessels 1-4 together : hard, 

 heavy. Plum, Prunus domistica, 

 ^* Heartwood yellowish-brown, with greenish streaks, 

 fragrant : vessels 1-8 together : hard. Mahaleb 

 Cherrv, Prunus Mahaleb, 



