JOIKXAI, Ol" I"()ki;STKV 



b Rcsiii ducts absent; as a ^-esult of injury, gum ducts with dark-red con- 

 tents may appear in a compact tangential row in certain species, 

 a' Woods with yellow color predominating; in some cases becoming 

 brown upon exposure to sunlight. Gum ducts not known to occur. 

 (f" Growth rings fairly distinct, due mostly to differences in density 

 but often accompanied by a tine limiting line of wotxl parenchyma; 

 no lines of parenchyma within growth rings. Pores very numer- 

 ous, small to minute, more or less clustered and often in short, 

 irregular, diagonal chains; tyloses abundant; gum and white de- 

 posits absent. Rays of the same color as the fibers; sometimes 

 storied producing fairly distinct ripple-mark^ (about lOO pe: 

 inch) ; rays not conspicuous on radial section. Wood rather light 

 but fairly hard. Color pale yellow or yellowish-brown. Pri.ma 

 \'i:r.\. "WiiiTK Mahoc.anv'' : Tabcbuia doiinoUesudtii ( Bignoni- 

 acea?). 

 b' Growtli rings absent or indistinct; density uniform. Pores of 

 fairly uniform size, rather numerous; sometimes subdivided ra- 

 dially but not arranged diagonally; usually surrounded by paren- 

 chyma. Ripple-marks absent. Color bright yellow at first, turn- 

 ing brown upon exposure, 

 rt' Pores rather large and prominent, surrounded by irregular 

 patches of parenchyma sometimes confluent for a short dis- 

 tance or even forming long tangential lines, prominent on all 

 sections ; white deposits common ; tyloses not abundant. Rays 

 of about the same color as the fibers in fresh wood; other- 

 wise lighter. Wood rather hard. Jackwood: Artocarpus iii- 

 tegrifoUa ( Urticacese). 

 b^ Pores medium-sized or rather small, usually associated with 

 parenchyma which may form short inconspicuous wings not 

 confluent into long lines : white deposits absent ; tyloses abun- 

 dant, appearing more or less gummy and making the vessel 

 lines very conspicuous. Rays considerably darker than wood 

 fibers. Color somewhat variegated or striped. Wood light 

 and soft; ratlier wooly-textured. Espave, "Espave AIahoc- 

 ANv": . I nacardiinn rhiuocarptis (.^nacardiacece). 

 /'' W(j()(ls with rcddisli, pinkish or purplish color predominating. Gum 

 ducts known to occur in several species. 

 a" Woods with aromatic scent like cigar-box cedar. 



(/^ Growth rings present. Wood parenchyma mostly in concen- 

 tric lines at limits of growth rings only. 

 (/* Woods mostly ring-porous or showing tendency to be- 

 come so; when strictly diffuse-porous (as in certain neo- 

 tropical species or varieties of Cedrela) growth rings are 

 marked by conspicuous light-colored line of parenchyma 

 showing plainly on all sections. Pores large to minute ; 

 mostly open; often subdivided; gum deposits present: 

 white substance not observed ; vessel lines usually very 

 prominent. Gum ducts occasionally present in prominent 

 dark-red streaks. Ravs fine but distinct on all sections. 



