50 OF WOOD IN GENERAL. 



Heartwood yellowish-brown. J. communis and J. OxycMrus. 



c. Very light, very soft, odourless. Heartwood light-red, 



turning brownish : sapwood narrow, amber-coloured. 

 Rings regular. Pith-rays very distinct, especially on 

 the radial section. Resin-canals in a single row, or 

 absent. "Redwoods," Sequoia. 



d. Medium heavy and hard, often camphor-scented. Heart- 



wood rich brown, often mottled with darker brown 

 or yellow : sapwood narrow, white. Rings wavy. 

 " Cypress Pines," etc. Cdllitris. 



e. Light, moderately hard, or soft, fragrant. Heartwood 



yellowish or reddish-brown. Rings well rounded. 

 Resin-ducts few and narrow. Cfclrus. 



3. Heartwood present, but differing only in shade from the sap- 

 wood, of a dull yellowish or greyish brown. 



a. Odourless and tasteless. Taxodium. 



b. Light, soft, with slight resinous odour, tasteless. Rings 



finely and coarsely wavy. Pith-rays very fine but 

 distinctly coloured. "White Cedars," including Thuya 

 occidentalis and T. gigdntea, Cupressus thyoides and C. 

 Lawsonidna. 



c. Light, soft, with resinous smell and peppery taste. Incense 



Cedar, Liboddrus. 



Near here belong apparently the Huon Pine and allied species, 

 Dacrf/dium, etc. 



B. Resin-canals present, at least in autumn wood. 



1. Heartwood not distinctly coloured, white: resin-canals few, 



very narrow : rings imperfectly rounded ; tracheids in pith- 

 rays. Spruces, Picea. 



2. Heartwood distinct. 



a. Resin-canals not numerous, nor evenly distributed. 



(i) Canals solitary or here and there in pairs ; tracheids 

 without spirals. Heartwood reddish-brown, sapwood 

 yellowish. Knots irregularly distributed. Larches 

 or Tamarack, Ldrix. 



