400 CONTRIBUTIONS PROM THE NATIONAL HERBARIUM. 



twice as many, inserted at the base of a disk; ovary superior, 1-celled, 1-ovuled, the 

 styles often 3, ultimately becoming a small dry drupelike fruit. 



Our species have all been recognized as belonging to one genus, Rhus, but they 

 are so different in general appearance that it seems best to follow Doctor Greene in 

 separating them into several genera, though the characters upon which the separa- 

 tion is based are mostly vegetative rather than floral. 



KEY TO THE GENERA. 



Flowers appearing before the leaves, in small crowded 

 clusters. 

 Leaves 1 or 3-foliolate; flowers yellow, tinged with red . 1. Schmaltzia (p. 406). 



Leaves 5 to 9-foliolate; flowers white 2. Rhoeidium (p. 408). 



Flowers appearing after the leaves, in their axils or in 

 panicles terminating the stems. 

 Leaves 3-foliolate, poisonous; generally under- 



; 1 nubs with slender stems 3. Toxicodendron (p. 408). 



Leaves pinnately several to many-foliolate, not 

 poisonous; shrubby plants with thick stems, 

 one species with hard wood 4. Rhus (p. 408). 



1. SCHMAI/TZIA Deav. Lemita. 



Widely branching shrubs, 2 meters high or less; leaves unifoliolate or trifoliolate, 

 the leaflets mostly cuneate-obovate, crenately and coarsely few-toothed, the terminal 

 ones often 3-lobed ; flowers yellow or reddish yellow, in crowded clusters on very short 

 peduncles on the branches of the previous season, appearing before the leaves; fruit 

 orange scarlet, globose, 4 to 6 mm. in diameter. 



The roots of these plants are used by the Indians in forming patterns for their 

 basketry. The bark is of a dark reddish brown color. The plants are also used in 

 setting dyes. Mexicans sometimes use the stems in making baskets, mixing them 

 with willow branches. The berries were used as food by some of the Indians. 



KEY TO THE SPECIES. 



Leaves unifoliolate 1 • S. affin is. 



Leaves trifoliolate. 



Young twigs densely velvety-pubescent with long yellowish 



hairs 2. S. emoryi. 



Young twigs merely puberulent or soft-pubescent, the hairs not 

 yellowish. 

 Bracts of the aments tomentose all over. 



Fruit densely long-hirsute; leaflets small, thick, nearly 



glabrous, at least on the upper surface 0. S. quercifolia. 



Fruit sparingly short-hirsute; leaflets large, thin, pubes- 

 cent on both surfaces 7. S. baker i. 



Bracts of the aments glabrous or glabrate, at least on the up- 

 per half. 

 Terminal leaflet abruptly contracted at the base, 



deeply 3-lobed 3. S. pulchella. 



Terminal leaflet, gradually cuneate at the base, shallowly 

 lobed. 

 Teeth of the leaves rounded; blades densely pu- 



beacenl ; all the leaflets toothed 4. 8. leiocarpa. 



Teetli of the leaves acutish; blades mostly glabrous 

 on the upper surface; some of the leaflets 

 entire 5. S. cognata. t 



