604 



TREES OF NORTH AMERICA 



inner surface by dark longitudinal lines; stamens rather shorter than the petals. 

 Fruit ripening in November and December, pendent in long graceful clusters, 

 orange-colored, rather lustrous, |' long; seed about \' long. 



A tree, with exceedingly acrid poisonous juice, frequently 35-40 high, with a 

 short trunk sometimes 2 in diameter, stout spreading often pendulous branches 



forming a low broad head, and reddish brown branchlets marked by prominent leaf- 

 scars and numerous orange-colored lenticels. Winter-buds large, rufous-pubescent. 

 Bark of the trunk about ^' thick, light reddish brown tinged with orange, often 

 marked by dark spots caused by the exuding of the resinous gum, and separating 

 into large thin plate-like scales displaying the bright orange color of the inner bark. 

 Wood heavy, hard, not strong, rich dark brown streaked with red, with thick light 

 brown or yellow sapwood of 25-30 layers of annual growth. The resinous gum 

 obtained from incisions made in the bark is emetic, purgative, and diuretic. 



Distribution. Shores of Bay Biscay ne and the keys of southern Florida; very 

 abundant; also in the Bahamas, Cuba, Jamaica, and Honduras. 



3. RHUS. K 



Trees or shrubs, with pithy branchlets, fleshy roots, and milky sometimes caustic 

 OP watery juice. Leaves unequally pinnate, or rarely simple. Flowers mostly dioe- 

 cious, rarely polygamous, white or greenish white, in more or less compound axil- 

 lary or terminal panicles, the staminate and pistillate usually produced on separate 

 plants; calyx-lobes united at the base only, generally persistent; disk surrounding 

 the base of the free ovary, coherent with the base of the calyx; petals longer thau 

 the calyx-lobes, inserted under the margin of the disk, opposite its lobes, deciduous; 

 stamens 5, inserted on the margin of the disk alternate with the petals; filaments 

 longer than the anthers; ovary ovoid or subglobose, sessile; styles 3, terminal, free or 

 slightly connate at the base, rising from the centre of the ovary. Fruit usually glo- 

 bose, smooth or covered with hairs; outer coat thin and dry, more or less resinous; 

 stone crustaceous or bony. Seed ovoid or reniform, commonly transverse; cotyledons 

 foliaceous, generally transverse; radicle long, uncinate, laterally accumbent. 



Rhus is widely distributed, with more than one hundred species, in the extra- 

 tropical regions of the northern and southern hemispheres. In North America the 

 genus is widely and generally distributed from Canada to southern Mexico and from 



