52 OF WOOD IN GENERAL. 



f Wide rings. Loblolly arid Short-leaf Pines of 



U.S.A., P, tu'da and P. echindta; Northern, 



Black Austrian, and Cluster Pines of Europe, 



P. sylvfatris, Laricio, and Pinaster. 



ft Narrower rings. Longleaf Pine of U.S.A., P. 



palustris ; Dwarf Pine of Europe, P. montdna. 

 (ii) Wood soft and light: transition from spring to 

 autumn wood gradual ; autumn wood narrower and 

 with fewer resin-canals : tracheids of pith-ray without 

 dentate projections. Soft Pines. 

 * Rings rather narrow, circular : resin-ducts very large 



and numerous : wood yellowish. P. Cdmbra. 

 ** Rings broad : wood redder. Weymouth and Sugar 

 Pines, P. Strdbus and P. Lambertidna of U.S.A. ; and 

 probably the Aleppo Pine, P. 



II. LEAF-WOODS, HARD- WOODS, OR POROUS WOODS. 



Pores visible on transverse section, either to the naked eye or 

 when magnified, often characteristically grouped, especially in 

 spring-wood. Pith-rays either all fine or some broad. 



A. Without distinct annual rings, though sometimes with 

 false-rings or partial zones of wood-parenchyma. Mostly 

 tropical. 



1 . With false rings. 



a. Some pith-rays broad. Indian Oaks, Qu6rcuslamelUsa, etc. 



b. All pith-rays narrow. 



(i) False rings very distinct. 



* No distinct heartwood : wood moderately hard and 

 dense, greyish. Banyan, Ficus bengaUnsis, Myro- 

 balans, TermimUia beUrica, and various Asiatic 

 Acacias and other Legumindscn. 



** Dark heavy heartwood. e.g. the very hard, tough 

 purplish-brown Jhand, Prosdpis spicigera. 



