DESCRIPTION OF PLATE V. 



Fig. 1 . — Morus rubra (red mulberry) : cross section showing arrangement of 

 pores in late wood, width of rays, and presence of tyloses in large pores. 



Fig. 2. — Fraxinus nigra (black ash) : cross section showing isolated pores in 

 late wood not joined tangentially by wood parenchyma. Outer margin of growth 

 ring composed of thin layer of wood parenchyma. 



Fig. 3. — Alnus oregona (red alder) : cross section showing aggregate ray and 

 distribution of pores. 



Fig. 4. — The same: tangential section showing aggregate ray, intermediate 

 uniseriate rays, vessels, wood fibres, and wood-parenchyma strands. 



Fig. 5. — Betula lenta (sweet or black birch) : cross section showing size and 

 distribution of pores and width of rays. Note wood-parenchyma cells, isolated 

 or in short tangential lines. 



Fig. 6. — Ostrya virginiana (hornbeam): cross section showing size and 

 arrangement of pores and distribution of wood-parenchyma cells in inconspicuous 

 tangential lines. 



