CLASS V. ORDER III. 127 



long or oval, entire, or sometimes slightly sinuate, acuminate, 

 smooth, paler underneath, nearly sessile, except the terminal 

 one. The flowers, which appear in June, are very small, green, 

 in loose axillary panicles. Where they appear not axillary, it is 

 because the leaf under them has been detached. The barren 

 and fertile flowers grow on different trees. The panicles of bar- 

 ren flowers are the largest and most branched. They are fur- 

 nished with short, oblong bracies, and downy pedicels. The 

 calyx has five ovate segments, and the corolla five oblong, sig- 

 moid petals. The stamens are longer than the petals, and pro- 

 ject through their interstices. The rudiment of a three-cleft 

 style is found in the centre. In the fertile flowers the calyx and 

 petals resemble the last, while the centre is occupied by an oval 

 germ, ending in three circular stigmas. The fruit is a bunch of 

 dry berries, or rather drupes of a greenish white, sometimes 

 marked with slight purple veins, and becoming wrinkled when 

 old. They are roundish, a little broadest at the upper end, and 

 compressed, containing one white, liard furrowed seed. 



The effluvium of this shrub is a violent poison to certain con- 

 stitutions, producing in them a distressing cutaneous eruption, 

 when it is handled or even approached. On others, and I believe 

 on a majority, it exerts no influence. The leaves have been 

 rubbed, chewed, and swallowed without injury. Their taste is 

 simply herbaceous and astringent, and does not indicate any ex- 

 traordinary quality. 



In Japan a fine varnish is said to be prepared from the juice 

 of the Rhus vernix, a tree, whose identity with the present is 

 doubtful. De Candolle has separated the American from the 

 Japanese plant, giving the former the name of R. venenata, which 

 name is adopted by Hooker and others. 



Rhus radicans. Poison Ivy, 



American Medical Botany, PI. xlii. 



Leaves ternate ; leafets petioled, ovate, naked, en- 

 tire ; stem rooting; flowers diojcious. 



A hardy climber, frequently seen running up trees to a great 

 height, supporting itself by lateral roots, and becoming nearly 

 buried in their bark. The leaves of the Rhus radicans are ter- 



