DESCRIPTION OF PLATE VI. 



FIG. 1. Liquidambar styraciflua (red or sweet gum): cross section showing 

 size and distribution of pores, width of rays, and arrangement of wood fibres in 

 radial rows. 



FIG. 2. Liriodendron tulipifera (yellow poplar or tulip- tree) : cross section 

 showing size and distribution of pores, and thin layer of wood-parenchyma cells 

 marking outer limit of growth ring. 



FIG. 3. Magnolia acuminata (cucumber tree): tangential section showing 

 vessels with scalariform bordered pits, and the small biseriate rays. 



FIG. 4. Liriodendron tulipifera: tangential section showing vessels with 

 ordinary bordered pits, and the comparatively large 3-5-seriate rays. 



FIG. 5. ^Esculus glabra (Ohio buckeye) : cross section showing uniform dis- 

 tribution of pores and rays. 



FIG. 6. The same: tangential section showing very fine uniseriate rays, 

 irregularly disposed. 



