DESCRIPTION OF PLATE IV. 



Fig. 1. — Hicoria ovata (shagbark hickory): cross section showing very thick- 

 walled wood fibres and distinct tangential lines of wood parenchyma; large pores 



with tyloses. 



Fig. 2. — Diospyros Virginia nn (persimmon): crns-s section showing rather in- 

 distinct tangential lines of wood parenchyma; pores without tyloses. 



Fig. o. — Hicoria pi can (pecan hickory): tangential section showing very 

 irregular rays, three large calcium-oxalate crystals, and numerous wood-paren- 

 chyma strands. 



Fig. 4. — Diospy/os virginiana : tangential section showing fairly uniform 

 rays in storied arrangement. Crystals visible, but very small. 



Fig. 5. — The same; radial section showing vessel segments, heterogeneous 

 rays, wood-parenchyma strands, and wood fibres in storied arrangement. 



Fig. 6. — Juglans nigra (black walnut): radial section showing rays, large 

 vessel with tyloses, wood-parenchyma strands, chambered-parenchyma cells with 

 crystals, and wood fibres. 



